<span>According to the formula :
</span><span>a=<span><span>ΔV / </span><span>ΔT
</span></span></span><span>When a body is moving with a uniform velocity, the acceleration is zero. That's it. You should remember, that velocity is not constant whereas speed is constant.</span>
Answer:
Explanation:
Given
mass of box 
speed of box 
distance moved by the box 
coefficient of kinetic friction 
Friction force 


Kinetic Energy of box will be utilize to overcome friction and rest is stored in spring in the form of elastic potential energy




Do you see that blank, open space after the word "potential ..." ?
There's supposed to be a number there that actually tells us the value of the potential. Without that number ... and a lot more description of the whole scenario here ... there's no possible answer to the question.
Answer:
W = - 5.01 10¹⁰ J
Explanation:
Work is defined by the expression
W = ∫ F.dr
Where the blacks indicate vectors, in the case the force is radial and the distance is also radial, whereby the scalar producer is reduced to an ordinary product
W = ∫ F dr
W = G m₁m₂ ∫ 1 /r² dr
W = G m₁ m₂2(-1 / r)
We evaluate between the lower limits r = Re and upper r = ∞
W = G m₁m₂ (-1 / Re + 1 / ∞)
W = - G m₁ m₂ / Re
Let's calculate
W = - 6.67 10⁻¹¹ 800 5.98 10²⁴ / 6.37 10⁶
W = - 5.01 10¹⁰ J