Which of the following gives the magnitude of the momentum change of the gas atom?
−F acting on object B.
−F acting on object A.
+F acting on object B.
+F acting on object A.
When the object has fallen to height `h/4` above the surface, what is
What is the speed of the object when t=15 s?
After 15 s the boy has run 50 m. What is his instantaneous speed and his average speed when t = 15 s?
X + Y + Z
m1 and m2 approach each other along a straight line with speeds v1 and v2 as shown. The objects collide and stick together.
What is the total change of linear momentum of the objects as a result of the collision?
m1v1 + m2v2
m1v1 – m2v2
m2v2 – m1v1
increases with time.
depends on the initial velocity only.
depends on the mass of the balls.
The object must be moving at constant speed.
The velocity of the object in any direction must be zero.
The forces acting horizontally on the object must equal the forces acting vertically on the object.
The resultant force acting on the object must be zero.
it moves in a circle with constant speed.
its acceleration is uniform.
the net internal force acting on it is zero.
the net external force acting on it is zero.
Which equation correctly relates W, P and R?
Direction of motion
Which of the following is the power of the engine?
ms–1. It rebounds horizontally with a speed of 3.0 ms–1. The ball is in contact with the wall for a time of 0.20 s.
What is the average magnitude of the force exerted by the ball on the wall?
If g = 10 m s–2, what is the initial speed of the object?
Rate of change of speed
Rate of change of velocity
The object must be stationary.
The object must be moving with constant acceleration.
There must be no external forces acting on the object.
10th floor and the 2nd floor at a constant speed. One main energy transformation during this journey is
gravitational potential energy → kinetic energy.
electrical energy → kinetic energy.
kinetic energy → thermal energy.
electrical energy → thermal energy.
The momentum of child Y is equal and opposite to the momentum of child X.
The speed of rotation of the Earth will have changed.
The ball has no net momentum while it is in the air.
The total momentum of the system has not changed.
t1 is also shown.
Which of the following gives the speed of the object at point P?
the gradient at P
the shaded area
`1/(gr adient atP`
Two railway trucks collide and they link together.
Two railway trucks collide and they do not link together.
Two gas molecules collide and each changes direction.
Two gas molecules collide and a bond is formed between them.
increases the time for which the force of the ground acts on the egg.
reduces the momentum of the egg.
reduces the change of momentum of the egg.
reduces the impulse acting on the egg.
1 has a kinetic energy E1. Another object has a mass m2 and kinetic energy E2. The objects have the same momentum. What is the ratio `E_1/E_2?`
The object is at rest at t = 0.
What is the speed of the object when t = 30 s?
0.18 m s–1
6 m s–1
12 m s–1
180 m s–1
6.0m s–1. What is the mass of the body?
Which expression gives the work necessary to maintain the constant velocity?
Chemical energy is converted into gravitational potential energy.
Chemical energy is converted into gravitational potential energy, sound and thermal energy.
Gravitational potential energy is converted into chemical energy.
Gravitational potential energy is converted into chemical energy, sound and thermal energy.
± 0.08 cm3
± 0.60 cm3
± 0.80 cm3
± 2.4 cm3
Which of the following statements is true?
The shaded area is equal to the force exerted by the wall on the ball.
The shaded area is equal to the force exerted by the ball on the wall.
The gradient is equal to the force exerted by the wall on the ball.
The gradient is equal to the force exerted by the ball on the wall.
What is correct about the horizontal distances travelled by X and Y and the times taken by X and Y to reach the ground?
The spheres undergo a head-on elastic collision.
Which statement correctly describes the spheres after the collision?
The total momentum of the spheres is 2mv.
Each sphere has zero momentum.
The total kinetic energy of the spheres is mv2.
Each sphere has zero kinetic energy.
I. The object is moving with uniform circular motion.
II. A force is applied to the object in the direction of its velocity.
III. A force is applied to the object in a direction opposite to its motion.
Which of the above statements is/are correct?
I and II only
I and III only
The resultant force on the body in any direction is zero.
The velocity of the body in any direction is zero.
No external force is acting on the body.
No work is done on the body.
ms–1 and experiences no frictional force. How far does the puck travel in 2.5 s?