A boy tries to hit a bird by throwing a stone vertically upward but the stone misses the bird. The stone goes upwards in the air for 3 s. While returning after 1 second the stone hits the bird. Answer the following questions based on the information given: (𝒊) Find the maximum height reached by the stone. (𝒊𝒊) At what height was the bird hit? (𝒊𝒊𝒊) What value is not shown by the boy? Open Answer »
Velocity-time graph for the ball’s motion is shown in figure. Observe the graph and answer the following questions. Assume that g = 10 m/s2 and that there is no air resistance. (a) In which direction is the ball moving at point C? (b) At which point is the ball stationary? (c) At which point is the ball at its maximum height? (d) what is the ball’s acceleration at point C? (e) What is the ball’s acceleration at point A? (f) What is the ball’s acceleration at point B? (g) At which point does the ball have the same speed as when it was thrown? Open Answer »
How does the force of attraction between the two bodies depend upon their masses and distance between them? A student thought that two bricks tied together would fall faster than a single one under the action of gravity. Do you agree with his hypothesis or not? Comment. Open Answer »
Identical packets are dropped from two aeroplanes-one above the equator and other above the north pole, both at height h. Assuming all conditions to be identical, will those packets take same time to reach the surface of earth? Justify your answer. Open Answer »
How does the weight of an object vary with respect to mass and radius of earth? In a hypothetical case, if the diameter of the earth becomes half of its present value and its mass becomes four times of its presents value, then how would the weight of any object on the surface of the earth be affected? Open Answer »
Define acceleration due to gravity. Derive an expression for acceleration due to gravity in terms of mass of the earth (M) and universal gravitational constant (G). Open Answer »
Derive expression for force of attraction between two bodies and then define gravitational constant. Open Answer »