Physics
(a) A truck and a car are running with the same speed on a highway. If the ratio of the kinetic energies is 25 : 12, then what is the ratio of their masses?
(b) Give two examples in which mechanical energy is conserved.
Related Questions
(a) State two characteristics that a medium should have for propagation of sound.
(b) A pendulum has a frequency of 4 vibrations per second. An observer starts pendulum and fires a gun simultaneously. He hears the echo from a cliff after 8 vibrations of pendulum. If the velocity of sound in air is 340 ms-1, then what is the distance between cliff and observer?
(a) Explain in brief the given statement — radioactivity is a nuclear phenomenon.
(b) What is meant by nuclear waste?
Shyam is trying to balance a meter rod on his finger as shown in the diagram. Two weight 50 gf and 200 gf at 40 cm and 95 cm respectively and his finger at 70 cm.
Find the anti-clock wise moment and clockwise moment.
(b) Find the weight of meter rod.
(a) Draw a diagram of a pulley system of velocity ratio 4. Calculate its mechanical advantage, if its efficiency is 90%.
(b) Why does a rope walker hold a long pole in his hands? Explain.