Question

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

Answer 1

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 :-)

Answer 2

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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