Answer:
56 J
Step-by-step explanation:
Formula to find the kinetic energy is :
E_kEk = \frac{1}{2}21 × m × v²
Here ,
m ⇒ mass
v ⇒ velocity
Let us solve now
E_kEk = \frac{1}{2}21 × m × v²
= \frac{1}{2}21 × 7 kg × ( 4 ms⁻¹ )²
= \frac{1}{2}21 × 7 × 16
= \frac{1}{2}21 × 112
= 56 J
Hope this helps you :-)
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