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A 2 kg object has a kinetic energy of 64 J. What is its momentum?

User Er Sahaj Arora
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1 Answer

13 votes
13 votes

Take into account that the momentum is given by:


p=mv

where m is the mass and v the speed of motion.

In order to calculate p it is necessary to find the value of v. Use the following expression for the kinetic energy:


K=(1)/(2)mv^2

In this case, you have:

K = 64J

m = 2 kg

Solve for v and replace the previous values:


\begin{gathered} v=\sqrt{(2K)/(m)} \\ v=\sqrt[]{\frac{2(64J)}{2\operatorname{kg}}}=8(m)/(s) \end{gathered}

Now, replace the value of v and m to find the momentum:


p=(2kg)(8(m)/(s))=16\operatorname{kg}\cdot(m)/(s)

Hence, the momentum is 16 kg*m/s

User Liamvictor
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3.1k points