Physics for IGCSE & O level - Forces And Motion (Section 13)
1
What is the unit for weight?
Trả lời
(B)
Newton (N)
2
What is friction?
Trả lời
(B)
The force that opposes motion between surfaces.
3
What is meant by 'uniform acceleration'?
Trả lời
(B)
Acceleration is constant.
4
Which of the following quantities has both magnitude and direction?
Trả lời
(D)
Velocity
5
Which of the following is a form of dynamic friction?
Trả lời
(D)
Sliding friction
6
What is the relationship between force and momentum?
Trả lời
(A)
Force is the rate of change of momentum.
7
If an object is moving at a constant velocity, what can you say about the forces acting on it?
Trả lời
(C)
The net force acting on the object is zero.
8
What can you say about the relationship between mass and acceleration, assuming a constant force?
Trả lời
(B)
Mass and acceleration are inversely proportional.
9
What does the area of the shaded triangle in the speed-time graph represent?
Trả lời
(D)
Distance
10
What is the net force acting on an object moving at a constant velocity?
Trả lời
(A)
Zero
11
What is the relationship between velocity and acceleration?
Trả lời
(B)
Acceleration is the rate of change of velocity.
12
What is the key idea behind the law of conservation of momentum?
Trả lời
(D)
Total momentum in a closed system remains constant.
13
The term "impulse" is best described as:
Trả lời
(A)
The change in momentum.
14
Which of the following is a correct unit for measuring force?
Trả lời
(C)
N
15
In the example of rocket propulsion, what is the action force?
Trả lời
(B)
The hot gases expelled downwards.
16
What is the defining characteristic of a closed system in physics, related to momentum?
Trả lời
(A)
No external forces.
17
What direction is acceleration in a circular motion?
Trả lời
(C)
Towards the center of the circle.
18
Which is a valid way to describe the motion of an object with uniform speed?
Trả lời
(C)
A straight, non-horizontal line on the distance-time graph.
19
Which of the following best describes Newton's First Law of Motion?
Trả lời
(B)
An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
20
In Newton's third law of motion, for every action there is an equal and opposite: