ICSE physics

Sponsor Area

Question
ICSEENIPH10005514

When a body is placed on a table top, it exerts a force equal to its weight downward on the table top but does not move or fall.

i) Name the force exerted on the table top.

ii) What is the direction of the force? 

Solution

i) Normal reaction force
ii) The force acts normal to the surface of the table top i.e., opposite to the direction of the force due to the weight of the body.

Sponsor Area

Question
ICSEENIPH10005515

b) i) What is the S.I unit of moment of force?

Solution

S.I. unit of the moment of force is Newton x meter (Nm) 

Question
ICSEENIPH10005516

Name the factors affecting the turning effect of a body? 

Solution

The factors affecting the turning effect of a body are:

i) The magnitude of a force applied.

ii) The distance of the line of action of the force from the axis of rotation. 

Question
ICSEENIPH10005517

On what factor does the position of the centre of gravity of a body depend? 

Solution

The position of center of gravity of a body of given mass depends on its shape, i.e., on the distribution of mass in it.

Question
ICSEENIPH10005518

How is work done by a force measured when the force:

i) is in the direction of displacement

ii) is at the angle to the direction of displacement.

Solution

i) Work done by a force when the force is in the direction of displacement.

That is equal to Force x Displacement of the point of application of the force in the direction of force.

ii) Work done by a force when the force is at an angle θ to the direction of displacement , 

= Force x component of displacement in the direction of force.

= Force x d cosθ