Physics Answers

Compare and contrast nuclear fission and fusion how are they the same and how are they different

Describe the three forms of thermal energy transfer.

 How do thermal energy, temperature and heat differ

The diagram below shows a horizontal beam of negligible mass. The wall exerts a

42.0 N horizontal force on the lever. Find the weight of the load.

note:

horizontal beam 1.80 m

vertical string is 1.30m at 28degrees

the load is at the end of the beam away from the wall

A 50 g slug slides down a 2.0 m long drain pipe. If the slug's speed at the bottom of the pipe is only 3.0 m/s, how much energy was dissipated as heat caused by friction?

A small sample of coal, when completely converted into energy, releases 3.75 * 10 ^ 14 j . What is the initial mass of coal, assuming the final mass 0

Use the table of specific heat capacities to solve this problem. A bar of aluminum is heated to 90.0C and then placed into 10.0L of water at 20.0 degrees * C the mixture cools to 22.4 degrees * C , what is the mass the aluminum bar? 

A 15-kg uniform beam is 3.0 m long and is pivoted 1.0 m from the left end. A 35 kg child sits on the left end of the beam 0.60 m from the pivot. How far from the pivot must a 20 kg child sit in order for the beam to be in equilibrium?

You hang an object by means of a vertical string. Two strings in turn support this string. String 1 and string 2 make 20o and 60o with the horizontal beam, respectively.

Find the tensions in the strings if the mass of the object is 75.0 kg.

A ladder 7.50 m long is leaning against a smooth (frictionless) wall at a point 7.0 m above the ground. The ladder weighs 200 N and an 800-N painter stands two thirds of the way up the ladder. What frictional force must act on the bottom of the ladder to prevent it from slipping for the painter to be safe?