Answer:
C
Explanation:
gravity is a pulling force according to Newton
Answer:
Because it is said that the earth rotates and revolves around the sun and moon so it is impossible for the earth not to be spinning.
Explanation:
#Case -1
If Pulling force is less than frictional force the object won't move .
#Case-2
If Pulling force is greater than frictional force then object will be .
In order to calculate friction force you need Limiting friction first .
u s is coefficient of static friction and N is normal reaction
Or
Answer:
(a) the time needs for her to cross the river is 2736.8 s.
(b) the distance takes to reach the other side of the river is 2490.5 m.
Explanation:
given information:
woman's speed, v₁ = 1.9 m/s
the wide of river, s = 5.2 km = 5200 m
river's current, v₂ = 0.91 m/s
(a) How much time does it take her to cross the river?
s = v t
s = the displacement (m)
v = speed (m/s)
t = time (s)
s = v t
t = s/v
= 5200/1.9
= 2736.8 s
(b) How far downstream will the river carry her by the time she reaches the other side of the river?
s = v t
= (0.91) (2736.8)
= 2490.5 m
The heat pump is a thermal machine that takes heat from a cold space and transfers it to a hotter one thanks to a work provided from the outside, that is, it does exactly the same as the refrigerating machine, the only thing that changes is the objective (In the refrigerating machine the objective is to cool and keep the cold space cold. The heat pump, however, aims to provide heat and keep the hot space warm)
Therefore the correct answer is A. <em>A heat pump uses work to transfer energy by heat from a colder environment to a warmer environment.</em>
