Answer: Shorter
Explanation: Shadow is formed when an light source is obstructed by an opaque object. The closer the source, shorter is the length of the shadow. In fact, when the source is exactly overhead, no shadow of the object is formed.
June 21 marks the Summer solstice which means the Sun passes directly overhead Tropic of cancer (23.5° N) at noon. March 21 marks the equinox which means sun passes directly overhead equator (0°).
Shadow length of an object at 42° Northern latitude will be shorter on June 21 because the Sun will be closer to this latitude as compared to March 21.
The height difference is found by

Then the change in potential energy is
That ratio is the efficiency of whatever the power went into and came out of. There's no reason the efficiency has to be expressed as a percentage.
Answer:
3.6km South East
Explanation:
Displacement is the shortest distance between the starting point and the ending point and the direction it is displaced in. To calculate the displacement we can use the pythagoras theorem because the 3km East and the 2km south form the two shorter sides of a right angled triangle between the starting and ending points. So, the displacement is the length C of the triangle which we can calculate as follows:
Pythagoras Theorem:
a^2+b^2=c^2
(2)^2+(3)^2=c^(2)
4+9=c^2
Square root 13 = c
c=3.6km (1dp)
The total displacement is 3.6km and is in the approximate direction of South East (because he travelled east and south).
Hope this helped!
Answer:
F = 8 N
Explanation:
The question says "The body is subjected to a force with a moment of 0.4 N × m shoulder - 5 cm. What is the magnitude of this force?
Given that,
Moment/Torque, 
Distance moved, d = 5 cm = 0.05 m
We need to find the magnitude of this force. We know that, the torque acting on an object is given by :

So, the magnitude of force is equal to 8 N.