Question

A body, under the action of a force F =6i - 8j +10k , acquires an acceleration of 1 m/s. The mass of
this body must be
(A) 10 kg
(B) 20 kg
(C) 10V2
(D) 2V10 kg

Answer 1

Take out the magnitude of Force.

That is the only trick point in this otherwise simple problem.

Answer 2

Answer:

(C)The mass of the body is

$m = 10 \sqrt{2} \: kg$

Explanation:

Given that,Body is under the action of force

$F=6i-8j+10k$

The magnitude of the force is

$|F| = \sqrt{6 {}^{2} + ({ - 8})^{2} + {10}^{2} } \\ = 10 \sqrt{2} \: N$

Also given the acceleration of the body is

$a = 1 \: ms {}^{ - 2}$

Now the mass of the body can be found using relation

$F=ma=>m=\frac{F}{a}$

Substituting known values,we get mass as

$m = \frac{10 \sqrt{2} }{1} = 10 \sqrt{2} \: kg$

#SPJ3