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goblinko [34]
2 years ago
6

3) Calculate the kinetic energy of a 7 kg mass traveling at a velocity of 4 m/sec.

Physics
2 answers:
Pepsi [2]2 years ago
7 0

Answer:

56 J

Explanation:

Formula to find the kinetic energy is :

E_k = \frac{1}{2}  × m × v²

Here ,

m ⇒ mass

v ⇒  velocity

Let us solve now

 E_k = \frac{1}{2} × m × v²

     = \frac{1}{2} × 7 kg × ( 4 ms⁻¹ )²

     = \frac{1}{2} × 7 × 16

     = \frac{1}{2} × 112

     = 56 J

Hope this helps you :-)

Let me know if you have any other questions :-)

murzikaleks [220]2 years ago
4 0

▪▪▪▪▪▪▪▪▪▪▪▪▪  {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪

Let's solve ~

Given terms :

  • Mass (m) = 7 kg

  • velocity (v)= 4 m/s

The formula to find kinetic Energy is ~

\boxed{ \boxed{ \sf{ \frac{1}{2}  m{v}^{2} }}}

Now, apply the formula according to given situation

{ \qquad{ \sf{ \dashrightarrow}}}  \:  \: \sf \: \dfrac{1}{2}  \times 7 \times ( {4)}^{2}

{ \qquad{ \sf{ \dashrightarrow}}}  \:  \: \sf \: \dfrac{1}{2}  \times 7 \times 16

{ \qquad{ \sf{ \dashrightarrow}}}  \:  \: \sf \:7 \times 8

{ \qquad{ \sf{ \dashrightarrow}}}  \:  \: \sf \:56 \:  \: joules

Therefore, the kinetic Energy of the car is 56 joules

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See the last 7 answers in the attached document.

Download docx
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