Question

a body is thrown up with a velocity of 20 m/s. It retards uniformly at the rate of 10 m/s2. find the velocity of the body after 2 sec.​

Answer 1

Given, initial velocity (u) = 20 m/s; retardation rate (-a) = 10 m/s^2; time = 2 sec.

Then, v = u + (-at)

or, v = 20m/s - 10m/s^2 × 2s

or, v = (20 - 20) m/s = 0 m/s (ans)

Answer 2

Aɴꜱᴡᴇʀ

☆ Velocity of the body = 0 m/s

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Gɪᴠᴇɴ

✭ Acceleration (a) = ( -10 m/s² )

✭ Time (t) = 2 seconds

✭ Initial velocity (u) = 20 m/s

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Tᴏ ꜰɪɴᴅ

➳ The final velocity of the body?

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Sᴛᴇᴘꜱ

➜ To find the answer let's use the First equation of motion, that is,

$\large{\underline{ \boxed{ \sf{v = u + at}}}}$

Calculating,

$\large \tt \leadsto{}v =20 + ( - 10) \times 2 \\ \\ \large \tt \leadsto{}v = 20 - 20 \\ \\ \large \tt \orange{ \leadsto{}v = 0 \: m/s}$

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