Question

If the momentum of a flying brick is $50{{kg\,m} \mathord{\left/ {\vphantom {{kg\,m} s}} \right.} s}$ and its mass is 10 kg, calculate its velocity.
A. $500m/s$
B. $2m/s$
C. $5m/s$
D. None

Answer 1

Hint
The given question is based on the concept of the linear momentum. The momentum is given by the product of the mass and velocity. So in the equation by substituting the values of the momentum and the mass we can find the velocity of the body.
In this solution we will be using the following formula,
$\Rightarrow \vec p = m \times \vec v$
where $\vec p$ is the momentum of a body,
$\vec v$ is the velocity of the body and $m$ is the mass.

Complete step by step answer
The formula for computing the linear momentum of the object is given by,
$\Rightarrow \vec p = m \times \vec v$
Where m is the mass of the object and v is the velocity of that object.
In the question we are given the values of parameters as the mass of the flying brick is $m = 10kg$ and the momentum of the flying brick is $\vec p = 50{{kg\,m} \mathord{\left/ {\vphantom {{kg\,m} s}} \right. } s}$.
Now by substituting these values in the equation of the momentum of the object, we can find the value of the velocity of the flying brick.
So, we get,
$\Rightarrow 50 = 10 \times \vec v$
Now by keeping only the velocity to the LHS we get,
$\Rightarrow \vec v = \dfrac{{50}}{{10}}$
On calculating we get the value of the velocity as,
$\Rightarrow \vec v = 5m/s$
$\therefore$ The velocity of a flying brick, given, the momentum of a flying brick is $\Rightarrow 50{{kg\,m} \mathord{\left/ {\vphantom {{kg\,m} s}} \right. } s}$ and its mass is 10 kg is $5m/s$.
Thus, the option (C) is correct.

Note
The linear momentum is the product of the mass of an object and its related velocity. The momentum is a vector quantity. The direction of the momentum is the same as that of the velocity. In simple words, the momentum can be defined as the inertia of motion or the mass in the motion.