Latent heat, energy absorbed or released by a substance during a change in its physical state (phase) that occurs without changing its temperature.
Answer:
(a) 81.54 N
(b) 570.75 J
(c) - 570.75 J
(d) 0 J, 0 J
(e) 0 J
Explanation:
mass of crate, m = 32 kg
distance, s = 7 m
coefficient of friction = 0.26
(a) As it is moving with constant velocity so the force applied is equal to the friction force.
F = 0.26 x m x g = 0.26 x 32 x 9.8 = 81.54 N
(b) The work done on the crate
W = F x s = 81.54 x 7 = 570.75 J
(c) Work done by the friction
W' = - W = - 570.75 J
(d) Work done by the normal force
W'' = m g cos 90 = 0 J
Work done by the gravity
Wg = m g cos 90 = 0 J
(e) The total work done is
Wnet = W + W' + W'' + Wg = 570.75 - 570.75 + 0 = 0 J
I'm pretty sure the answer is d.The weight of the book and the table's upward force on the book are equal in magnitude but opposite in direction.
The answer is b. The crest.
Hope this helps!
Answer:
Explanation:
We shall apply concept of impulse to solve the problem .
Impulse = force x time
impulse = change in momentum
force x time = change in momentum
initial speed u = 24 km/h = 6.67 m /s
final speed v = 65 km/h = 18.05 m /s
change in momentum = m v - mu
= m ( v-u )
= 1350 ( 18.05 - 6.67 )
= 15363 kg m/s
F x 18 = 15363
F = 853.5 N .
