A constant force acting on a body of mass of 5 kg change its speed from 5 m s-1 to 10 ms-1 in 10 s without changing the direction of motion. The force acting on the body is

Question

A constant force acting on a body of mass of 5 kg change its speed from 5 m s-1 to 10 ms-1 in 10 s without changing the direction of motion. The force acting on the body is (A) 1.5 N (B) 2 N (C) 2.5 N (D) 5 N

Tardigrade Admin · Accepted Answer

Here, m=5 Kg, u=5 m s-1, v=10 m s-1, t=10 s Using v=u+a t a=(v-u/t) =((10-5)m s-1/10 s) =0.5 m s-2 As F=ma ∴ F=(5 kg) (0.5 m s-2) =2.5 N

Q. A constant force acting on a body of mass of $5 k g$ change its speed from $5 m s^{- 1}$ to $10 m s^{- 1}$ in $10 s$ without changing the direction of motion. The force acting on the body is

$1.5 N$

$2 N$

$2.5 N$

$5 N$

Here, $m = 5 K g$ ,
$u = 5 m s^{- 1}$ ,
$v = 10 m s^{- 1}$ ,
$t = 10 s$
Using $v = u + a t$
$a = \frac{v - u}{t}$ $= \frac{( 10 - 5 ) m s ^{- 1}}{10 s}$
$= 0.5 m s^{- 2}$
As $F = ma$
$∴$ $F = (5 k g)$ $(0.5 m s^{- 2})$
$= 2.5 N$

Q. A constant force acting on a body of mass of 5kg change its speed from 5ms−1 to 10ms−1 in 10s without changing the direction of motion. The force acting on the body is

1.5N

2N

2.5N

5N