Which of the following actions describe pushing force?
Kicking is a pushing action while the others are pulling actions.
Which of the following is NOT a force?
Chemical energy is not a force.
A force is applied on an object in the direction of its motion. What is the effect of force on the object?
Since, the force is applied in the direction of motion of the object, the speed of the object will increase.
If no force acts on a body at rest, then what effect can be observed?
In the absence of a force, a body will remain at rest (static object) or move with uniform velocity.
Which of the following examples describe the change of shape on applying force?
We apply certain force to tear a paper. The shape of the paper changes after it is repeatedly torn into pieces.
Which of the following effects is caused by frictional force?
Frictional force between two surfaces tends to decrease the speed of a moving object.
Which of the following is a non-contact force?
The electrostatic force is a non-contact force.
What causes the atmospheric pressure?
Atmospheric pressure is caused by the weight of air molecules surrounding the earth.
How does the pressure exerted by a liquid change?
The pressure exerted by a liquid increases with depth.
As we go we deeper in a liquid the pressure of liquid increases. As the depth of liquid increases the weight of liquid column pushing down from above increases and hence the pressure also increases.
What is thrust equal to?
Thrust is the total force applied on a given area. It is given as the product of pressure and area.
A When does a body float on water?
The weight of a body is balanced by the upthrust of water. Hence, the net force acting on a body is zero and so this helps the body float.
In which of the following cases the net force is NOT equal to zero?
When a ball is falling freely from a height, the net force is not equal to zero.
We use a straw (narrow pipe) to drink juice from a glass. What make this possible?
When we suck air from pipe, atmospheric pressure pushes the liquid juice up to fill the vacuum and it comes up.
Which of the following effects is NOT caused by the magnetic force between a magnet and a magnetic substance?
A magnet attracts a magnetic material thereby making it move from rest. There may be a temporary change in the shape or size. But there is no change in the chemical composition.
In cities, water from an overhead tank is supplied to houses using the principle of
(i) difference in pressure.
(ii) gravitational force.
(iii) decrease of friction m pipes.
The water at a height flows down due to pressure and gravitational force.
A deep sea diver's ears get hurt when he is inside the water. What is the cause for it?
Water pressure increases with an increase in the depth of the sea which effects the diver's ears.
What does a barometer measure?
The barometer is used to measure atmospheric pressure of a place.
Four forces are acting on a body. If the body does not change its position or shape/then what does it mean?
For a body to be in equilibrium or at rest, the vector sum of all forces must be zero.
Why do deep sea divers use a special suit for diving?
The suit (known as scuba suit) is pressurized to counter balance the heavy pressure in deep sea.
On what factors does the magnitude of non-contact force depend?
The magnitude of non-contact force depends on the distance between two bodies, mass and chemical composition of the two bodies.