Answer:
option (c) - 10 j
Explanation:
F = (6 i + 4 j - 2 k) N
r1 = (1.5, 3, -4.5) m = (1.5 i + 3j - 4.5 k) m
r2 = (4, -2.5, - 3) m = (4 i - 2.5 j - 3 k) m
displacement, r = r2 - r1 = ( 2.5 i - 5.5 j + 1.5 k) m
Work done is defined as the dot product of force vector and teh displacement vector.
W = (6 i + 4 j - 2 k) . ( 2.5 i - 5.5 j + 1.5 k)
W = 15 - 22 - 3 = - 10 J
When she starts out, he is (40x2.5)= 100 miles ahead of her.
She gains (65-40)= 25 miles on him every hour.
It takes her (100/25)= 4 hours to catch up to him.
Answer:
Explanation:
The PE equation for a mass/spring system is
Δx² and filling in:
and
so
k = 26000 N/m
If the displacement from equilibrium changes more, the PE needed to compress it will also change.
gives us that
PE = 520J