The forklift does no work on the box at all.
And work doesn't have a direction.
Answer:
Change in electric potential energy ∆E = 365.72 kJ
Explanation:
Electric potential energy can be defined mathematically as:
E = kq1q2/r ....1
k = coulomb's constant = 9.0×10^9 N m^2/C^2
q1 = charge 1 = -2.1C
q2 = charge 2 = -5.0C
∆r = change in distance between the charges
r1 = 420km = 420000m
r2 = 160km = 160000m
From equation 1
∆E = kq1q2 (1/r2 -1/r1) ......2
Substituting the given values
∆E = 9.0×10^9 × -2.1 ×-5.0(1/160000 - 1/420000)
∆E = 94.5 × 10^9 (3.87 × 10^-6) J
∆E = 365.72 × 10^3 J
∆E = 365.72 kJ
Answer:
P=2736 Pa
Explanation:
According to Newton we have that:
∑
A force is exerted by the elevator to the suitcase, according to 3th Newton's law an equal force but in the opposite direction will appeared on the suitcase, that is:
∑

We know that the pressure is given by:
work done=446.9 J . so option (c) is correct.
Explanation:
the formula for work done is given by
W= F d
F= force= mg where m= mass and g= acceleration due to gravity
F= 3.8 (9.8)=37.24 J
so W=37.24 (12)
W=446.9 J