Question

A man of mass $30\,kg$ uses a rope to climb which bears only $450\,N$ . What is the maximum acceleration with which he can climb safely?
A. \[10\,m{\text{ }}{s^{ - 2}}\]
B. $15\,m{\text{ }}{s^{ - 2}}$
C. $20\,m{\text{ }}{s^{ - 2}}$
D. $25\,m{\text{ }}{s^{ - 2}}$

Answer 1

Hint: To solve this question, we must have a concept of Newton’s second law of motion and then we can easily solve this question. Here we simply substituted the given values in the formula to obtain the required solution. The force acting on a body is equal to the rate of change of momentum, according to Newton's second law of motion.

Formula used:
$F = ma$
Where, $F$ is the force, $m$ is the mass and $a$ is the acceleration.

Complete step by step answer:
According to the question, mass is $30\,kg$ and force is $450\,N$. And we know that from the second law of motion,
$F = ma$
Now, substituting the above given values in the formula, and solving for acceleration,
$F = ma \\
\Rightarrow 450 = 30 \times a \\
\therefore a = 15\,m{\text{ }}{s^{ - 2}} $
Thus, the maximum acceleration with which he can climb safely is $15\,m{\text{ }}{s^{ - 2}}$ .

Hence the correct option is A.

Note: The first law of motion is related to Newton's second law of motion. It provides a numerical definition of force. It describes the causes and effects of force and changes in motion of an item mathematically. Before learning how to solve the equation for Newton's second law of motion, which deals with an object's force, mass, and acceleration.