ICSE physics

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Question
ICSEENIPH10005741

A boy weighs 360 N on Earth.

i) What would be his approximate weight on the moon?

ii) What is the reason for your answer?

Solution

i) Weight of the body on the moon is one-sixth of the weight of the body on the earth.

Weight of the body = 1/6 x Weight of moon = 1/6 x 360 = 60 N

ii) W = mg
And, acceleration due to gravity on moon as one-sixth that on the earth. Therefore, weight on the moon is also one-sixth of the earth. 

Sponsor Area

Question
ICSEENIPH10005742

A body is acted upon by a force. State two conditions under which the work done could be zero. 

Solution

The two conditions are:

i) Displacement is zero.

ii) Angle between force and displacement is 90o.

Question
ICSEENIPH10005743

A spring is kept compressed by a small trolley of mass 0.5 kg lying on a smooth horizontal surface as shown in the figure:



When the trolley is released, it if found to move at a speed of 2 m/s. What potential energy did the spring possess when compressed?     

Solution

Error converting from MathML to accessible text. 

Question
ICSEENIPH10005744

i) Define the term momentum.

ii) How is force related to the momentum of a body?

iii) State the condition when the change in momentum of a body depends only on the change in its velocity. 

Solution

i) Momentum is defined as the product of mass and velocity of a body.

ii) Force  = Rate of change in momentum

straight F space equals space increment straight P divided by increment straight t space
iii) When velocity of the body is much smaller than the velocity of light, then the mass is constant. 

Question
ICSEENIPH10005745

A body of mass 50 kg has a momentum 3000 kg m/s. Calculate:

i) the kinetic energy of the body.

ii) the velocity of the body. 

Solution

Given,

Mass, m = 50 kg

Momentum, p = 3000 kg m/s 
                  P = m × v
Error converting from MathML to accessible text.