Physics Answers

Two fire trucks are moving toward each other at a rate of 25 m/s. If the first

fire truck emits a frequency of 10000Hz and the ambient temperature is 400C,

what will be the observed frequency of the second fire truck?

A trumpet emits a sound frequency equivalent to 100Hz. If the person using

the trumpet is moving towards the listener, what would be the perceived

frequency of the listener if the velocity of the sound is 350 m/s and the man

using the trumpet is moving at the rate of 5 m/s?

A car is moving at a rate of 50 m/s when suddenly the driver hit the horn that

emits 20000Hz frequency. What will be the perceived frequency of a man

standing at the sidewalk if the speed of the sound is 340 m/s and the car is

moving away from the location of the man?

Find the specific gravity and the density of an object with a dimension of 25cm

x 60cm x 80 cm with a mass of 9000g.

Suppose you heat 1,000 g of water to boiling and mix it with 3,000 g of water at 160C contained in an aluminum pail of mass 50 g. What is the temperature of the resulting mixture? Show your complete solution.

The temperature in your body is 750F. If the answer is 23.90C in Celsius scale and 296.9K in Kelvin scale, how will you get these answers?

1.  A boy weighing 150 N goes up and down a flight of stairs. The vertical distance between the floor is 5.5 m. How much work is done by gravity?

The density of gold at 20°C is 19,300kg/m3. Find the density at 100°C?

Find the change in entropy when 3.0 kg of water is heated from 20°C to 80°C?

Two forces, F1= 8.0 N, 60 degrees northwest and F2= 12.0 N, southwest, are applied to a particle at the origin. What third force is needed so that the particle will not be displaced from the origin?