1. State and give mathematical expression of universal law of gravitation.
2. The weight of an object is 98N on earth, calculate its mass and weight on moon.
3. Give four points of difference between mass and weight.
4. A stone is released from top of a tower of height 49 m. Calculate it's final velocity just before touching the ground.
5. When an object is thrown from a height it move towards earth, why the earth does not move towards object.
Answers
Answer:
1.The force is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In equation form, this is F=GmMr2 F = G mM r 2 , where F is the magnitude of the gravitational force. G is the gravitational constant, given by G = 6.673 × 10−11 N·m2/kg2
2.Thus, the mass of the body is 10 kg, which always remains constant. (b) Let weight on moon is W'. W' = mass × acceleration due to gravity on the Moon. W' = 10 × 1.6 =16 N.
3.The difference between mass and weight is that mass is the amount of matter in a material, while weight is a measure of how the force of gravity acts upon that mass. Mass is the measure of the amount of matter in a body. ... Weight usually is denoted by W. Weight is mass multiplied by the acceleration of gravity (g).
Answer:
2. Solution : W = mg
W = 98 N
g = 9.8 m/s2
m = W
g
=
98
9 8. = 10 kg.