Question

5. Velocity of a body is changed from 2m/s to 8m/s. Find
i) change in velocity
ii)fractional change in velocity
iii) percentage of change in velocity

Answer 1

Given:

Velocity of a body is changed from 2m/s to 8m/s.

To find:

• Change in velocity
• Fractional change
• % change

Calculation:

CHANGE IN VELOCITY:

$\sf \: \Delta v = v2 - v1$

$\sf \implies \: \Delta v = 8 - 2$

$\sf \implies \: \Delta v = 6 \: m {s}^{ - 1}$

FRACTIONAL CHANGE:

$\sf \: \dfrac{\Delta v}{v1} = \dfrac{6}{2} = 3 \: m {s}^{ - 1}$

% CHANGE:

$\sf \: \dfrac{\Delta v}{v1} \times 100\% = 3 \times 100\% = 300\%$

Hope It Helps.

Answer 2

Explanation:

(i) Change in velocity

[ Given: v2 = 8m/s & v1 = 2m/s ]

=>Δv = v2 - v1

=>Δv = 8 - 2

.°. Δv = 6m/s

(ii) Fractional Change in velocity

=> Δv/v1 = 6/2 = 3m/s

.°. Δv/v1 = 3m/s

(iii) % of Δv

=> Δv/v1 × 100%

=> 6/2 × 100%

=> 3 × 100%

=> 300%

.°. 300%