2.2 Forces
A check for understanding on the IBDP Physics topic 2.2 Forces.
Question 1
Two blocks X and Y rest on a frictionless horizontal surface as shown. A horizontal force is now applied to the larger block and the two blocks move together with the same speed and acceleration.
Which free-body diagram shows the frictional forces between the two blocks?
A
B
C
D
Question 2
A box is accelerated to the right across rough ground by a horizontal force Fa. The force of friction is Ff. The weight of the box is Fg and the normal reaction is Fn. Which is the free-body diagram for this situation?
A
B
C
D
Question 3
A person who weighs 500 N is standing on a scale in an elevator. In both cases, the elevator is identical and is moving upward. However, in case A the elevator is accelerating upward and in case B the elevator is accelerating downward. This means the reading on scale A would be greater than the reading on scale B.
Question 4
A parachutist of total mass 70 kg is falling vertically through the air at a constant speed of 8 m/s.
What is the total upward force acting on the parachutist? (Give correctly rounded value + space + Unit)
Question 5
Two forces act on an object in different directions. The magnitudes of the forces are 18 N and 27 N. The mass of the object is 9.0 kg. What is a possible value for the acceleration of the object?
0 m/s/s
0.5 m/s/s
2.0 m/s/s
6.0 m/s/s
Question 6
Two stationary objects of mass 1 kg and 2 kg are connected by a thread and suspended from a spring. The thread is cut. Immediately after the cut, what are the magnitudes of the accelerations of the objects in terms of the acceleration due to gravity g?
* This is an AHL question
A
B
C
D
Question 7
A mass is suspended from the ceiling of a train carriage by a string. The string makes an angle θ with the vertical when the train is accelerating along a straight horizontal track.
*This is an AHL question
A
B
C
D
Question 8
Curling is a game played on a horizontal ice surface. A player pushes a large smooth stone across the ice for several seconds and then releases it. The stone moves until friction brings it to rest. The graph shows the variation of speed of the stone with time. The total distance travelled by the stone in 17.5 s is 29.8 m. Determine the coefficient of dynamic friction between the stone and the ice during the last 14.0 s of the stone’s motion. (Round to 3SF)
*This is an AHL question