Added potential energy = (mass) x (gravity) x (height)
or
Added potential energy = (weight) x (added height)
If you need to lift a 15N box 3m straight up, you have to increase its potential energy by (15 N) x (3 m) = 45 Joules .
Where is that added potential energy supposed to come from ? You could use an electric winch, a steam engine, a gasoline-powered motor, thousands of hamsters running on little treadmills that are are connected to the main pulley somehow, or your own arm muscles. But howEVER you do it, you have to provide <em>45 Joules</em> of WORK in order to increase the potential energy of the box by just that much.
Answer:
R=0.5B+0.5C+2A+D
Explanation:
By the triangular law of vector addition
vector R= vector B- vector D
As A,B,C,D are edges of the parallelogram,
A is parallel to D but opposite in direction.
Therefore
;
;
B is parallel to C and in same direction.
Answer:
ΔU = - 9,179 10-11 J
Explanation:
For this exercise the two basketballs are linked by gravitational interaction, so we can use gravitational energy
U = - G m₁m₂ / R
In this case the mass is equal and the initial distance is r₁ = 19 cm = 0.19 m
U₁ = - G m² / r₁
let's calculate
U₁ = - 6.67 10⁻¹¹ 0.55² / 0.19
U₁ = - 10,619 10⁻¹¹ J
when its centers are separated it is at r₂ = 1.4 m
U₂ = - 6.67 10⁻¹¹ 0.55² / 1.4
U₂ = - 1.44 10-11 J
the energy between these two points is
ΔU = U₂ - U₁
ΔU = (-1.44 +10.619) 10-11
ΔU = - 9,179 10-11 J
Answer:
The black cow takes in more of the sun than the white cow does. It absorbs the heat faster.
Explanation:
