Physics Answers

A 200 kg load is hung on a wire having a length of 4 m, cross-sectional area 1.2 x10-4 m2 , and Young‘s modulus 8 x 1010 N/m2 . What is its increase in length?

A particle P is projected from a point O with an initial velocity of 70m/s at an angle 30° to the horizontal. At the same instant a second particle Q is projected in the same direction, 20m from point O with initial speed 25m/s from a point level with O. If Particle Q is displaced to 90m from point of release C. If the particles Q collide with P at 80m from the point of release C, find the angle of projection of Q and find when the collision occurs.

an ideal refrigeration cycle is operating between 120 kPa and 1200 kPa. if R134a is the refrigerant, what is the compression work?

The electric potential difference between the ground and a cloud in a particular 

thunderstorm is 1.2X10^9 V. In the unit of electron- volt, what is the magnitude of the 

electric potential energy of an electron that moves between ground and the clouds?

Three +0.12C charges from an equilateral triangle 1.7m on a side. Using energy supplied

At the rate of 0.83KW, how many days would be required to move one of the charges to

the midpoint of the line joining the other two charges?

A force of 20N pulls two carts tied together with a string. The carts with masses 3kg and 4kg, respectively, run on a smooth level surface. Find :

a. The acceleration of the 4kg cart.

b. The acceleration of the 3kg cart.

c. The tension on the string connecting the two carts.

Please show the complete solution.

Doppler effect formula

A particle P is projected from a point I with an initial velocity of 70m/s at an angle of 30° to the horizontal. At the same instant, a second particle Q is projected in the same direction, 20m from point I with initial speed 25m/s from a point level with O. If particle Q is displaced to 90m from point of release C. If the particle Q collides with P at 80m from the point of release C, find the angle of projection of Q and find when the collision occurs.

In a cheerdancing competition, a 65.0 kg cheerleader is tossed vertically upward

with a speed of 3.75 m/s. a) what is the initial momentum of the cheerleader at

the moment she was tossed up? b) what is her momentum just before being

caught, assuming she was caught at the same height? c) what is the change in

momentum of the cheerleader?

A runner jogs 12 km north then turns and runs 16 km east in three hours. What is his displacement? Calculate his average speed. Calculate his average velocity (including the direction).