Science: Matter, Force, and Motion
Covers states of matter, phase changes, force, and laws of motion
Questions
What is the push or pull applied on any object to do any work called?
- Motion
- Force
- Speed
- Velocity
- Friction
Which of the following actions does not show any effect of force?
- Football is kicked
- Applying brakes in a car
- Turning handle of a cycle to turn
- Changing the colour of wall
- Stretching a rubber band
A force equal in magnitude and opposite in direction is called ____________.
- balanced force
- unbalanced force
- frictional force
- gravitational force
- none of these
If the resultant of applied forces is always_________, the forces are called unbalanced forces.
- zero
- less than zero
- more than zero
- equal to one of the forces
- equal to frictional force
Assertion(A): When the pile of coins on the carrom-board is hit by a striker; only the coin at the bottom moves away, leaving rest of the pile of coins at same place.
Reason(R): Coin at the bottom comes in motion, while rest of the coins in the pile have tendency to remain in rest and they vertically fall on the carrom board and remain at the same place.
- Both A and R are correct and R is correct reason for A
- A is correct but R is incorrect
- Both are correct but R is not the correct reason for A
- Both A and R are incorrect
- A is correct and R is incomplete reason
Before hanging the wet clothes over laundry line, usually many jerks are given to the clothes to get them dried quickly. Because of the jerks, droplets of water in the pores of the cloth _______________.
- gradually reduce in size
- evaporate
- fall down
- spread evenly
- join together and fall down
Newton's second law of motion states that, ''The rate of change of momentum is _____________''.
- directly proportional to F in the direction of force
- inversely proportional to F in the direction of force
- inversely proportional to F in the opposite direction of force
- directly proportional to F in the opposite direction of force
- directly proportional to F and independent of direction of force
While catching a cricket ball, the momentum of ball is _________ when it is stopped immediately after coming in the hands of fielder.
- reduced to zero suddenly
- increased suddenly
- reduced gradually
- increased gradually
- is not effected
To move a cupboard weighing 70 kg, force applied is 250 N. The frictional force exerted on the cupboard will be ___________.
- (250 x 70) N
- 70 N
- 250 N
- (250 + 70) N
- (250 - 70) N
Which of the following statements regarding unbalanced force is false?
(a) Moves a stationary object.
(b) Increases the speed of a moving object.
(c) Decreases the speed of a moving object.
(d) Stops a moving object.
(e) Cannot change the shape and size of an object.
- a
- b
- c
- d
- e