Question

work equal to 25joule is done on a mass of 2 kg to set it in motion. if whole of it is used to increase the kinetic energy then velocity gained by the mass in m/s is​

Answer 1

ɪ ʜᴏᴩᴇ ɪᴛ ᴡɪᴩʟ ʜᴇʟᴩ yᴏᴜ...

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Answer 2

Given:

• Work done is 25 Joule
• Mass of object = 2 kg.

To find:

• Velocity gained by object ?

Calculation:

In this type of questions, always apply WORK-ENERGY THEOREM :

• The theorem states that the work done by all forces will be equal to the change in kinetic energy.

$W = \Delta KE$

$\implies \: W = \dfrac{1}{2} m {v}^{2} - 0$

$\implies \: W = \dfrac{1}{2} m {v}^{2}$

$\implies \: 25 = \dfrac{1}{2} \times 2 \times {v}^{2}$

$\implies \: {v}^{2} = 25$

$\implies \: v = 5 \: m {s}^{ - 1}$

So, the gain in velocity (∆v)

= v - u

= 5 - 0

= 5 m/s

So, velocity gained is ∆v = 5 m/s.