Question

a body is moving vertically upwards its velocity changes at a constant rate from 50m s-1 to 20 m s-1 in 3second. what is its acceleration?​

Answer 1

Answer:

Given:

Initial Velocity = 50 m/s

Final Velocity = 20 m/s

Time taken = 3 sec.

To find:

Acceleration of the body

Concept:

Acceleration refers to instantaneous change in velocity with respect to time . It's a vector Quantity having both directions and magnitude.

Calculation:

$acc = \dfrac{change \: in \: velocity}{time}$

$= > acc = \dfrac{20 - 50}{3}$

$= > acc = \dfrac{ - 30}{3}$

$= > acc = - 10 \: m {s}^{ - 2}$

So final answer :

$\boxed{ \huge{ \red{ \bold{acc = - 10 \: m {s}^{ - 2} }}}}$

Important things to note :

• Negative sign indicates opposite direction of acceleration as compared to velocity
• It's also called Retardation or Deceleration.

Answer 2

Answer:

Given:

• A body is moving vertically upwards its velocity changes at a constant rate from 50m s-1 to 20 m s-1 in 3second.

Find:

• What is its acceleration?

Note:

• Acceleration is the charge of velocity for a unit of time.

• Velocity is vector measurement it's rate of thr direction of a motion.

• -ve signs refers the opposite direct of the acceleration, this -ve signs are known as Retardation.

Using formula:

• Acceleration = Charge of velocity/Time.

Calculations:

• Acceleration = 20 - 50/3

• Acceleration = -30/3 = -10 m/s⁻²

Therefore, -10 m/s⁻² is the acceleration.