Forces, density and pressure — AS & A Level Physics (9702) questions by topic

What is always conserved in elastic collisions? total kinetic energy total velocity --- --- --- A yes yes B yes no C no yes D no no

Two blocks K and L slide towards each other along a horizontal frictionless surface. Block K has momentum 0.72 kg m s^-1 to the right; block L has momentum 0.46 kg m s^-1 to the…

Which row describes a pair of forces that forms a couple? direction of the forces magnitude of the forces --- --- --- A opposite different B opposite equal C same different D same…

A uniform cylinder of weight 25.0 N is suspended from a newton meter. The cylinder is fully submerged in water, as shown. The reading on the newton meter is 10.0 N. The water is…

A student balances a 30 cm ruler on a fulcrum set at the 15 cm mark. She then places a 50 g mass on the 23 cm mark and a 20 g mass on the 11 cm mark. Which mass should she place…

A submarine is at a depth of 130 m below the surface of the sea. The pressure on the submarine due to the sea water is p. The submarine sinks to a depth of 260 m below the…

Which statement does not describe an elastic collision between two objects? A The relative speed of approach of the two objects equals the relative speed of separation. B The…

An empty cart is moving along a horizontal track at a constant velocity. Resistive forces acting on the cart are negligible. A heavy rock is dropped vertically into the cart. The…

A wooden block is held stationary in a container of water using a string that is attached to both the wooden block and the bottom of the container. The wooden block has mass m and…

A square shop sign of uniform density has mass 2.4 kg and sides of length 0.86 m. The sign is supported by a hinge along its top edge. There is friction in the hinge so that the…

A block is submerged vertically in a liquid. The four diagrams show the block viewed from the side. Which diagram shows, to scale, the forces exerted on equal areas of the block…

The diagram shows a couple: two equal and opposite forces separated by a perpendicular distance. How is the torque of the couple calculated? A ½ × perpendicular distance between…

A non-uniform bar PQ has weight 200 N. A block of weight 400 N is placed on the bar at P. The bar is lifted by an upward force of 360 N at Q. The bar is in equilibrium. What is…

What is the definition of density? A density = mass / area B density = mass × volume C density = weight / volume D density = mass / volume

A block is in equilibrium on a slope. Three forces act on the block: its weight W acting vertically downwards, the normal contact force N perpendicular to the slope, and the…

A measuring cylinder contains liquid to the 80 cm³ mark. The pressure exerted by the liquid at the 60 cm³ mark is 1200 Pa. What is the pressure exerted by the liquid at the base…

The diagram shows two fixed pins, Y and Z. A length of elastic is stretched between Y and Z and around pin X, which is attached to a trolley. X is at the centre of the elastic and…

Which statement about a couple is correct? A It acts to produce both translational motion and rotation. B It acts to produce rotation only. C It acts to produce translational…

A picture frame hangs from a string. The string is supported by a pin. The frame is in equilibrium. Which diagram shows the vector triangle of forces acting on the picture frame?

A solid metal cuboid of density 2700 kg m⁻³ has sides of lengths 1.0 m, 2.0 m and 4.0 m. The cuboid can be placed on a horizontal surface so that it rests on any one of its six…

A cylindrical iceberg of height H floats in sea water. The top of the iceberg is at height h above the surface of the water. The density of ice is ρᵢ and the density of sea water…

State the principle of moments.

Define the moment of a force about a point.

A ball of mass 0.25 kg is dropped from a height h₁ above the ground. The ball hits the ground and then bounces back up to a height h₂. Just before hitting the ground the ball has…

Define the moment of a force about a pivot.

State the principle of conservation of momentum.

Define the moment of a force.

Define momentum.

A thin horizontal plate of area 0.036 m² is beneath the surface of a liquid of density 930 kg m⁻³. The force on one side of the plate due to the pressure of the liquid is 290 N.…

Spheres X and Y form an isolated system. The mass of Y is greater than the mass of X. Sphere Y is initially stationary. Sphere X collides elastically with sphere Y. The speed of…

A ball of mass 0.10 kg is thrown towards a stationary vertical bat. The ball hits the bat with a horizontal velocity of 20 m s⁻¹. The ball rebounds and leaves the bat with a…

An isolated object of negligible weight is acted on by two coplanar forces of the same magnitude. In which diagram is the object in equilibrium? A one force acting downwards on…

A uniform beam PQ rests horizontally on a support at point S. The beam PQ is 2.5 m long; the support S is 0.30 m from end Q. A rope is attached at end P of the beam. The rope is…

The diagram shows the dimensions of an elastic cord used to project a stone. The tension in the cord is T when the cord is pulled into the shape shown. Each half of the cord is 10…

Two satellites in deep space collide inelastically. What happens to the total kinetic energy and total momentum? total kinetic energy total momentum --- --- --- A conserved…

What is a reasonable estimate of the momentum of a family car travelling at 25 kilometres per hour? A 1 × 10⁴ kg m s⁻¹ B 1 × 10⁵ kg m s⁻¹ C 1 × 10⁶ kg m s⁻¹ D 1 × 10⁷ kg m s⁻¹

A lead pellet is shot vertically upwards into a clay block that is stationary at the moment of impact, but is able to rise freely after impact. The mass of the pellet is 5.0 g and…

Two forces act on an object. Which diagram represents a couple? A two parallel 6 N forces acting downwards at different points on the object B a 6 N force downwards at one point…

The diagram shows a uniform rod, XY, that is freely hinged to a vertical wall at end Y. The rod is at an angle of 60° to the wall. A force F acts at an angle of 30° to the rod at…

Water has a density of 1.0 g cm⁻³. Glycerine has a density of 1.3 g cm⁻³. A student measures out a volume of 40 cm³ of glycerine into a container. The student adds water to the…

A block is moving along a horizontal frictionless surface. A constant force F and a constant resistive force of 5.0 N act on the block as it is moving in the direction of the…

Which statement about a perfectly elastic collision between two objects is correct? A Total kinetic energy is conserved and the relative speed of approach equals the relative…

The diagram shows the view from above of a sprinkler system used to water a garden. The sprinkler consists of a tube of length 0.15 m. The tube is pivoted in the middle and spins…

An object is held in equilibrium by three forces. The forces all act in the same plane. The diagram shows two of the forces that act on the object: a 43 N force and a 17 N force…

The total number of forces acting on an object is two. The object is in equilibrium. Which statements about the forces are correct? 1 The two forces must have equal magnitudes. 2…

The diagram shows the arrangement of atoms in a particular crystal. Each atom is at the corner of a cube. The mass of each atom is 3.5 × 10⁻²⁵ kg. The density of the crystal is…

Four measuring cylinders are filled with the same liquid to the heights shown. Position A is at the top surface of liquid filled to 30 cm; position B is at a depth such that 30 cm…

State the principle of conservation of momentum.

A ladder is positioned on icy (frictionless) ground and is leant against a rough wall. At the instant of release it begins to slide. Which diagram shows the directions of the…

A stationary ball of mass m is hit by a bat. The ball leaves the bat with velocity v. The bat is in contact with the ball for a short time delta t. What is the average force of…

A disc of mass M is moving across a horizontal frictionless surface with constant velocity u. It collides with a stationary disc of mass 4M. The diagram shows the view from above…

A solid sphere, which is less dense than water, is held completely immersed in water a few metres below the surface. The density of the water is uniform. The sphere is released.…

A uniform bar of weight 200 N and length 4.0 m is freely hinged on a wall at one end. The bar is horizontal and is held in equilibrium by a cable attached at a distance of 0.50 m…

The diagrams all show a pair of equal forces acting on a metre rule. Which diagram shows forces that provide a couple and zero resultant force? [Four diagrams A-D each showing a…

A ball of mass 2.0 kg travels horizontally with a speed of 4.0 m s^-1. The ball collides with a wall and rebounds in the opposite direction with a speed of 2.8 m s^-1. The time of…

A kite is in equilibrium at the end of a string. The kite has three forces acting on it: the weight W, the tension T in the string, and the force F from the wind. Which vector…

Four forces act about a point P, as shown. A horizontal arm of length 7.0 m has a 6.0 N upward force at its left end; a 5.0 N force acts at point X above P and an inclined arm…

A rectangular block of lead of density 1.13 x 10^4 kg m^-3 has sides of length 12.0 cm, 15.0 cm and 10.0 cm. What is the maximum pressure the block can exert when resting on a…

Four cuboids with identical lengths, breadths and heights are immersed in water. The cuboids are held at the same depth and in identical orientations by vertical rods. Water has…

The graph shows the variation of the momentum p with time t for a car. p rises linearly from 1 x 10^4 kg m s^-1 at t = 0 to 4 x 10^4 kg m s^-1 at t = 20 s, stays constant until t…

A uniform beam of mass 1.4 kg is pivoted at P. The beam has a length of 0.60 m and P is a distance of 0.20 m from one end. Loads of 3.0 kg and 6.0 kg are suspended at distances of…

The diagrams show three rigid objects P, Q and R being subjected to different combinations of forces. Object P: 10 N to the left and 20 N to the right along the top, 20 N to the…

The diagram shows two liquids, labelled P and Q, that do not mix. The liquids are in equilibrium in an open U-tube. Three equal distances x are labelled. Liquid P occupies the top…

Define density.

Define linear momentum.

Define momentum.

State the principle of conservation of momentum.

State the principle of moments.

A snooker ball of mass 0.20 kg has a collision so that its direction of movement changes by an angle of 90 degrees, as shown. Before the collision the ball moves horizontally to…

Which statement about collisions is correct? A Kinetic energy is conserved in all collisions. B Momentum is only conserved in perfectly elastic collisions. C The relative speed of…

A satellite uses two thrusters to adjust its motion in space. Each thruster exerts a force of 40 N on the satellite. The line of action of each force is a perpendicular distance…

The diagrams show two ways of hanging the same picture. In both cases, a string is attached to the same points on the picture and looped symmetrically over a nail in a wall. The…

An object shaped as a hemisphere rests with its flat surface on a table. The object has radius r and density rho. The volume of a sphere is (4/3) pi r^3. Which average pressure…

A probe is used to monitor the quality of the water in the sea. The probe is suspended by a vertical string which is attached to a sphere. The stationary sphere floats in…

A uniform beam AB is attached by a hinge to a wall at end A, as shown in Fig. 3.1. The beam has length 0.50 m and weight W. A block of weight 12 N rests on the beam at a distance…

Two forces, each of 10 N, act at a point P, as shown. The angle between the directions of the forces is 120 degrees. What is the magnitude of the resultant force? A 5 N B 10 N C…

A camera drone of mass 1.20 kg hovers at a fixed point above the ground. The drone has four propellers. In a time of 1.00 s, each propeller pushes a mass of 0.400 kg of air…

An object of mass m, moving at speed u along a frictionless horizontal surface, collides head-on with a stationary object of mass 4m. After the collision, the object of mass m…

The driver of a car applies two parallel forces to a steering wheel, as shown. Each force has a magnitude of 15 N and acts in the direction shown (each at 65 degrees to the…

A farmer is trying to lift the corner of a large water tank. She uses a metal rod as a lever, with a pivot between the tank and the farmer's end. The vertical force from the…

The diagram shows a ball of weight W hanging in equilibrium from a string. The string is at an angle theta to the vertical. The tension in the string is T. The ball is held away…

Which expression for pressure is correct? A force per unit area B force per unit volume C mass per unit area D mass per unit volume

A ball has a mass of 0.50 kg and a volume of 1.3 x 10^-3 m^3. The ball is floating in equilibrium on still water. The two forces that act on the ball are its weight and the…

A stone sinks in water. What is a possible value for the density of the stone? A 8 x 10^2 kg m^-3 B 2 x 10^3 kg m^-3 C 8 x 10^3 N m^-3 D 2 x 10^4 N m^-3

A rod is pivoted at point O. A force F is applied to the rod at point W, as shown. X is the far end of the rod, and Y is the foot of the perpendicular from O to the line of action…

A uniform rod XY of weight 10.0 N is freely hinged to a wall at X. It is held horizontal by a force F acting from Y at an angle of 30 degrees to the horizontal, as shown. What is…

Two solid cubes X and Y are made of material of the same density. Cube X has twice the mass of cube Y. Cube X has sides of length x. Cube Y has sides of length y. What is the…

A U-shaped glass tube contains liquid of density 2000 kg m^-3. Level P in one arm is 10.0 cm above the bottom region; level Q in the other arm is 6.0 cm above the bottom region; P…

A device for spraying paint consists of a box with its faces horizontal and vertical. One of its vertical faces contains small holes. Paint is fed into the box under pressure via…

A uniform metre rule is pivoted at the 34.0 cm mark, as shown. The rule balances when a 64 g mass is hung from the 4.0 cm mark. What is the mass of the metre rule? A 38 g B 44 g C…

A volume of 1.5 m^3 of water is mixed with 0.50 m^3 of alcohol. The density of water is 1000 kg m^-3 and the density of alcohol is 800 kg m^-3. The volume of the mixture is 2.0…

An object is falling at a constant speed through a viscous liquid. FU is the upthrust on the object due to the liquid. WL is the weight of the liquid displaced by the object. WO…

A rigid uniform beam of weight W is connected to a fixed support by a hinge, as shown in Fig. 2.1. A compressed spring exerts a total force of 8.2 N vertically upwards on the…

A beaker in air contains a liquid. The base of the beaker is in contact with the liquid and has area A. The liquid has density rho and fills the beaker to a depth h. By using the…

Define pressure.

A block is pulled by a force X in a straight line along a rough horizontal surface, as shown in Fig. 3.1. Assume that the total resistive force opposing the motion of the block is…

A sphere floats in equilibrium on the surface of sea water of density 1050 kg m^-3, as shown in Fig. 2.1. 21% of the volume of the sphere is below the surface of the water.…

State the principle of conservation of momentum.

A ball of mass 200 g is thrown horizontally with a speed of 20 m s^-1 against a vertical wall. The ball is in contact with the wall for a time of 0.10 s before rebounding back…

Two objects move towards each other along the same straight line. After colliding, the two objects stick together and are stationary. Which statement must be correct? A The total…

A minimum torque of 20 N m must be applied to the lid of a jar for it to open. The radius of the lid is 4.0 cm. Two forces F act tangentially on opposite sides of the lid forming…

A uniform bar of length L and weight W rests horizontally on two supports X and Y. Support X exerts a vertical force RX at a distance of L/6 from one end of the bar. Support Y…

A type of firework is made by connecting two rockets, facing in opposite directions, to a rod. The rod is attached to a frictionless pivot so that the firework can rotate in a…

An object of weight W is suspended from a newton meter. When the object is completely immersed in water, the newton meter reads P. When the object is completely immersed in oil,…

An aeroplane is moving at a constant speed in a straight line at an angle theta to the horizontal. Four forces act on the aeroplane: thrust force T, weight W, lift force L and…

A force F is applied at an angle of 45 degrees to a door handle at a distance d from the pivot of the handle. What is the moment of the force about the pivot? A Fd / sqrt(2) B Fd…

A couple consists of two forces, each of magnitude F, that act in opposite directions in the same plane. The perpendicular distance between the two forces is d. What is the torque…

The diagram shows an experiment to determine the force exerted on a ball by a horizontal air flow. The ball is suspended by a light string and weighs 0.15 N. The deflection of the…

Two solid cylindrical objects X and Y are held fully submerged in a liquid. The objects have the same volume. The density of the material of Y is twice the density of the material…

A snooker ball has a mass of 200 g. It hits the cushion of a snooker table and rebounds along its original path. The ball arrives at the cushion with a speed of 14.0 m s^-1 and…

A ball falls from rest through air and eventually reaches a constant velocity. For this fall, forces X and Y vary with time as shown: force X rises from zero and approaches a…

An object X of mass 0.30 kg is travelling in a straight line at a constant velocity of 3.0 m s^-1 on a horizontal frictionless surface. Object X collides with a stationary object…

A uniform rigid beam of length 3.2 m is pivoted at its centre. Two children sit at the opposite ends of the beam. One child has a mass of 24 kg. The other child has a mass of 36…

Two parts of a sailing boat are the mast and the boom. The mast is a vertical rigid beam and the boom is a horizontal rigid beam. One end of the boom is attached to the mast by a…

Full-fat milk is made up of fat-free milk mixed with fat. A volume of 1.000 x 10^-3 m^3 of full-fat milk has a mass of 1.035 kg. It contains 4.00% fat by volume. The density of…

Which expression for pressure is correct? A force per unit area B mass per unit area C mass per unit volume D weight per unit volume

A hot-air balloon floats just above the ground. The balloon is stationary and is held in place by a vertical rope, as shown in Fig. 2.1. The balloon has a weight W of 3.39 x 10^4…

A high-altitude balloon is stationary in still air. A solid sphere is suspended from the balloon by a string, as shown in Fig. 2.1 (not to scale). The volume of the balloon is 7.5…

A ball Y moves along a horizontal frictionless surface and collides with a ball Z, as illustrated in the views from above in Fig. 4.1 and Fig. 4.2. Ball Y has a mass of 0.25 kg…

State the conditions for a system to be in equilibrium.