Question

A)Describe the motion of an object in which it speed is constant what the velocity is changing ?

b)Can the average speed ever be zero? Explain?
c)Explain the condition of the velocities of the two bodies in motion when:
i)there velocity are added for relative velocity
ii)there velocity are subtracted for relative velocity
d)What is indicated by the statement" acceleration of a body is 10m/s²?
e)Describe the conditions when the acceleration of a body is positive,negative and zero?
f)what is the value of acceleration in the following conditions?
i)When a body thrown upwards in maximum height
ii)When a body comes as it initial position after motion
iii)When a body gains a velocity of 60 m/s within 5 second from the rest position
iv)When a body moves with constant velocity
v)When a body falling downwards strike the ground
g)Which formula will you use to calculate relative velocity of a body in the following conditions?
i)If two boys are running in the same directions from the same references point
ii)If two girls are running in opposite directions from the same reference point
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Answer 1

a) If an object is moving at a constant speed but changing its direction, its velocity is changing too. Velocity includes both speed and direction, so even if the speed remains the same, a change in direction means the velocity is different.

b) Yes, the average speed of an object can be zero. This happens when the object travels a certain distance and then returns to its starting point, resulting in a total distance of zero and an average speed of zero.

c) i) When you add the velocities of two bodies to find the relative velocity, it means that one body is moving in relation to the other. The relative velocity is calculated by adding their individual velocities together.

ii) When you subtract the velocities of two bodies to find the relative velocity, it means that one body is moving in relation to the other. The relative velocity is calculated by finding the difference between their individual velocities.

d) If the statement says "acceleration of a body is 10 m/s²," it means that the body's velocity is increasing by 10 meters per second every second. In other words, for each passing second, the body's velocity increases by 10 meters per second.

e) The acceleration of a body can be positive, negative, or zero depending on its motion. If the body is speeding up in a specific direction, the acceleration is positive. If the body is slowing down in a specific direction, the acceleration is negative. If the body maintains a constant velocity (neither speeding up nor slowing down), the acceleration is zero.

f) i) When a body is thrown upwards to its maximum height, its acceleration is negative due to the force of gravity.

ii) When a body returns to its initial position after motion, its acceleration depends on how it got there. It can be positive, negative, or zero.

iii) When a body achieves a velocity of 60 m/s within 5 seconds from a resting position, its acceleration is 12 m/s² (calculated as 60 m/s divided by 5 s).

iv) When a body moves with a constant velocity, its acceleration is zero.

v) When a body falling downward hits the ground, its acceleration is negative due to the impact.

g) i) If two boys are running in the same direction from the same starting point, you would use the formula for relative velocity by subtracting their velocities.

ii) If two girls are running in opposite directions from the same starting point, you would use the formula for relative velocity by adding their velocities.

Answer 2

a) When an object's speed is constant, but its velocity is changing, it means that the object is changing direction. For example, a car driving in a circle at a constant speed is changing velocity, because its direction is constantly changing.

b) Yes, the average speed can never be zero. This happens when the object is moving in a straight line and its distance traveled is zero. For example, if a car drives from point A to point A, its average speed is zero.

c) The condition of the velocities of the two bodies in motion when:

i) their velocity is added for relative velocity: The relative velocity of two bodies is the velocity of one body relative to the other. If the velocities of the two bodies are added, the relative velocity will be the velocity of the first body plus the velocity of the second body.

ii) their velocity is subtracted for relative velocity: The relative velocity of two bodies is the velocity of one body relative to the other. If the velocities of the two bodies are subtracted, the relative velocity will be the velocity of the first body minus the velocity of the second body.

d) The statement "acceleration of a body is 10m/s²" indicates that the body is increasing its velocity by 10m/s every second. For example, if a body is moving at 10m/s and its acceleration is 10m/s², then after one second it will be moving at 20m/s, and after two seconds it will be moving at 30m/s, and so on.

e) The acceleration of a body is positive when the body is speeding up, negative when the body is slowing down, and zero when the body is moving at a constant velocity.

f) The value of acceleration in the following conditions:

i) When a body is thrown upwards in maximum height: The acceleration of a body thrown upwards in maximum height is zero. This is because the body is not moving at any velocity at the maximum height.

ii) When a body comes to its initial position after motion: The acceleration of a body coming to its initial position after motion is zero. This is because the body is not moving at any velocity at the initial position.

iii) When a body gains a velocity of 60 m/s within 5 seconds from the rest position: The acceleration of a body gaining a velocity of 60 m/s within 5 seconds from the rest position is 12m/s². This is calculated by dividing the change in velocity by the time taken.

iv) When a body moves with constant velocity: The acceleration of a body moving with constant velocity is zero. This is because the body is not changing its velocity.

v) When a body falling downwards strikes the ground: The acceleration of a body falling downwards strikes the ground is 9.8m/s². This is the acceleration due to gravity.

g) The formula to calculate the relative velocity of a body in the following conditions:

i) If two boys are running in the same direction from the same reference point: The relative velocity of two boys running in the same direction from the same reference point is equal to the sum of their velocities.

ii) If two girls are running in opposite directions from the same reference point: The relative velocity of two girls running in opposite directions from the same reference point is equal to the difference of their velocities.