REVISION QUESTIONS
!!!!Do it yourself!!!
1. What force F is necessary to push a block up a rough inclined plane at a constant
velocity?
2. A 0.510-kg book is held against a wall by pressing it against the wall with a force of 25.0
N. What must be the minimum coefficient of friction between the book and the wall, such
that the book does not slide down the wall?
3. State Newton’s laws of motion and explain their limitations
4. Distinguish between a Force of kinetic friction and Force of static friction
5. The two masses mA = 2.00 kg and mB = 20.0 kg are connected as shown. The table is
frictionless. Find (a) the acceleration of the system, (b) the velocity of mB at t = 3.00 s,
and (c) the position of mB at t = 3.00 s.
6. Two blocks 𝑚1 = 20.0 kg and m2 = 10.0 kg are connected as shown on a frictionless
plane. The angle θ = 25.00 and φ = 35.00. Find the acceleration of each block and the
tension in the connecting string.
7. A 0.150-kg ball is thrown straight upward at an initial velocity of 30.0 m/s. Two seconds
later the ball has a velocity of 10.4 m/s. Find (a) the initial momentum of the ball, (b) the
momentum of the ball at 2 s, (c) the force acting on the ball, and (d) the weight of the ball
8. Thermal energy can be transferred from one body to another by any or all of the
following mechanisms: Convection, conduction and radiation. Explain each mechanism
9. A hot air heating system is rated at 8.40 × 107 J/hr. If the heated air in the furnace
reaches a temperature of 120 0C, the room temperature is 15.6 0C, and the fan can
deliver 7.00 𝑚3 /min, what is the thermal energy transfer per hour from the furnace to the
room, and the efficiency of this system? The specific heat of air at constant pressure is c
air = 1009 J/kg 0C and the density of air is ρ = 1.29 kg/𝑚3 .
10. State the Stefan-Boltzmann Law and explain Why is it desirable to wear light colored
clothing in very hot climates rather than dark colored clothing