Physics Answers

8. A 1.50 x 103 kg car starts from rest and accelerates uniformly to 18.0 m/s in 12.0 s. Assume that air resistance remains constant at 4.00 x 102 N during this time. Find a) the average power developed by the engine and b) the instantaneous power output of the engine at t=12.0 s, just before the car stops accelerating.

An electron is accelerated from rest to a speed 0.8c by applying potential difference. Find it's value.

Light travels from air (n = 1) into glass, where its velocity reduces to 2x108 m/s. What is the index of refraction for glass? Take speed of light in air to be 3x108 m/s

Difference between heat and water

What is the speed of sound in air if its temperature is 560°C

Find the steady-state temperature in a bar whose ends are located at x = 0 and
x = 15, if these ends are kept at 200°C and 100°C respectively. (Use Fourier series)

A charge q is uniformly distributed on the surface of a cube and there is no other charge in consideration. Divergence of electric field is-

(a) zero inside the cube
(b) zero outside the cube
(c) zero on the surface of the cube
(d) zero nowhere.

A ski hill is inclined at 30 degrees. When a skier goes down the hill, his speed at the bottom is half the value expected in the absence of friction. What is the coefficient of kinetic friction between the skier and the hill?