Question
Can static friction do nonzero work on an object? If yes, give an example. If no, give reason.
✓
Answer
Yes. Let us consider a block A which is resting on another block B. Block B is resting on a smooth horizontal surface. Let the coefficient of kinetic friction between the blocks be $\mu\text{k}.$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
The benches of a gallery in a cricket stadium are 1m wide and 1m high. A batsman strikes the ball at a level one metre above the ground and hits a mammoth sixer. The ball starts at 35m/s at an angle of 53° with the horizontal. The benches are perpendicular to the plane of motion and the first bench is 110m from the batsman. On which bench will the ball hit?
Figure shows a man of mass 60kg standing on a light weighing machine kept in a box of mass 30kg. The box is hanging from a pulley fixed to the ceiling through a light rope, the other end of which is held by the man himself. If the man manages to keep the box at rest, what is the weight shown by the machine? What force should he exert on the rope to get his correct weight on the machine?
Explain why,
- A horse cannot pull a cart and run in empty space.
- Passengers are thrown forward from their seats when a speeding bus stops suddenly.
- It is easier to pull a lawn mower than to push it.
- A cricketer moves his hands backwards while holding a catch.
What do you understand by resonance? Explain the sharpness of resonance of a driven oscillator. Mention some phenomena related to resonance in daily life.
The potentiometer wire AB shown in the figure. is 40cm long. Where should the free end of the galvanometer be connected on AB so that the galvanometer may show zero deflection?
A steel rod 100cm long is clamped at its middle. The fundamental frequency of longitudinal vibrations of the rod are given to be 2.53 kHz. What is the speed of sound in steel?
Find the value of $\frac{\text{i}_1}{\text{i}_2}$ in the figure. if (a) $\text{R}=0.1\Omega$ (b) $\text{R}=1\Omega$ and (c) $\text{R}=10\Omega.$ Note from your answers that in order to get more current from a combination of two batteries, they should be joined in parallel if the external resistance is small and in series if the external resistance is large, compared to the internal resistance.
→
Figure shows a smooth track which consists of a straight inclined part of length 1 joining smoothly with the circular part. A particle of mass m is projected up the incline from its bottom.
- Find the minimum projection-speed v0, for which the particle reaches the top of the track.
- Assuming that the projection-speed is 2v0 and that the block does not lose contact with the track before reaching its top, find the force acting on it when it reaches the top.
- Assuming that the projection-speed is only slightly greater than v0, where will the block lose contact with the track?
A person travelling in a fast spaceship measures the distance between the earth and the moon. Is it the same, smaller or larger than the value quoted in this book?
In the given progressive wave $\text{y}=5\sin(100\pi\text{t+0.4x})$ where y and x are in m, t is in s. What is the:
Particle velocity amplitude.
→Particle velocity amplitude.