Question

Define acceleration. Give its mathematical formula and SI unit. When is acceleration of a body negative? Give two examples of situations in which acceleration of the body is negative.

Answer 1

Answer:

acceleration is the rate of change of velocity

a = v/t

S I unit is m/s

Examples for acceleration negative:

1. a ball thrown upward. Here a is negative (-9.8 m/s a constant)

2. when a car is decreasing its speed a becomes negative

Answer 2

Answer:

Acceleration:-

acceleration is the rate of change of velocity. Usually, acceleration means the speed is changing, but not always. When an object moves in a circular path at a constant speed, it is still accelerating, because the direction of its velocity is changing.

formula:-

Acceleration (a) is the change in velocity

a = Δv/Δt

negative acceleration:-

According to our principle, when an object is slowing down, the acceleration is in the opposite direction as the velocity. Thus, this object has a negative acceleration

Example:-

• When we apply brakes in a moving car, then negative acceleration acts on it and the car stops.

• When we throw a ball upwards, then also negative acceleration acts on it. Thus, when the ball reaches the highest point, the velocity of the ball becomes zero.

hope it will help you.....