Question

time taken by a man to cover 100m with a speed of 5m/s is
a.5 sec
b.10 sec
c.20 sec
d.80 sec​

Answer 1

Required Solution:

→ Option C

_____________

Given:

• Distance = 100 m

• Speed = 5m/s

To calculate:

• Time taken

Calculation:

As we know that,

$\boxed{\sf{v = \dfrac{s}{t} } }$

$\boxed{\sf{v \times t = s }}$

★$\boxed{\sf{t = \dfrac{s}{v} }}$

Where,

› v = spees

› t = time

› s = distance

Inserting values, we get:

→ t = $\sf{\dfrac{100}{5} \: sec}$

→ t = 20 sec

Therefore, time taken by a man to cover 100m with a speed of 5m/s is 20 sec. Option C is correct.

_______________________________

Extra Information:

☛ Distance is defined as the total path covered by the body.

☛ SI unit of distance is metre(m).

☛ Distance is a scalar quantity.

☛ Formula : $\boxed{\sf{v \times t = s} }$

☛ Speed is defined as distance covered per unit time.

☛ SI unit of speed is m/s.

☛ Speed is a scalar quantity.

☛ Formula : $\boxed{\sf{v = \dfrac{s}{t} }}$

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Answer 2

We know,

$\boxed{t = \dfrac{s}{v}}$

Distance = 100 m

Speed = 5 m/s

∴ $t = \dfrac{100 \ m}{5 \ ms^{-1}}$

⇒ t = 20 s (answer).

∴ (C) is the correct option of the question.

More:-

Equations of linear kinematics:-

1. $v_f = v_i + at$
2. $∆x = v_i t + \frac{1}{2} at^2$
3. $2a∆x = {v_f}^2 - {v_i}^2$