Work done is when a force is exerted to cause a displacement in a certain object.
the equation for work done ;
work done = force applied * displacement of the object
when the force applied is not in the same direction as that of the displacement of the object then the effect of the force is not its whole value. The force is then applied at an angle to that of the displacement of the object, then the resultant force is the force exerted* cos of the angle between force and displacement, in this instance the angle is 40 °.
the new equation is then;
work done = force cos 40° * displacement
after substitution,
work = 25 N * 0.76 * 50 m
= 957.55 J
round it off
= 9.6 *10² J
the correct answer is B
Almost right. protons are positive and electrons are negative. so when you run the balloon on your hair, electrons are transferred between them (i’m not sure which direction) and now one is positively charged as it lost negative particles and one is negative as it gained negative particles (electrons). opposite charges attract
1. Velocity
2. Time
3. Idk
4. Idk
5. D. I think it may be A. but I think D.
Answer:L=109.16 m
Explanation:
Given
initial temperature 
Final Temperature 
mass flow rate of cold fluid 
Initial Geothermal water temperature 
Let final Temperature be T
mass flow rate of geothermal water 
diameter of inner wall 

specific heat of water 
balancing energy
Heat lost by hot fluid=heat gained by cold Fluid




As heat exchanger is counter flow therefore





heat lost or gain by Fluid is equal to heat transfer in the heat exchanger
(LMTD)




Why do transformers hum? Transformer noise is caused by a phenomenon which causes a piece of magnetic sheet steel to extend itself when magnetized. When the magnetization is taken away, it goes back to its original condition. This phenomenon is scientifically referred to as magnetostriction.