Mechanics | Relativity Answers

A muon has a lifetime of 2*10-6 s in its rest frame. It is created 100 km above the earth and moves towards it at a speed of 2.97*108 ms-1 .At what altitude does it decay ? What is the distance travelled by the muon during this time in its own frame of reference?

Using the forces of adhesion and cohesion, explain why water has a concave meniscus and mercury has a convex meniscus.

a ball is thrown vertically upward. it has a sped of 10m/s when it has reached of its maximum heighr. how does the ball rise??

Hi
I need some ideas to create "handmade things" that show physics (holliday mechanics & electromagnetic) rules. You can use any material. More creative, cheaper and easier is better.
Mojtaba

Determine how much farther a person can jump on the moon as compared to the earth if the takeoff speed and angle are the same. The acceleration due to gravity on the moon is one sixth what it is on earth

Jed was driving his car at 40km/hr on a subdivision where the speed limit is 20km /hr. He was spotted by an officer in a motorcycle, who accelerates in pursuit. By the time jed sees the officers motorcycle it was traveling at 60km/ hr. What is the officer's velocity relative to jed car.

a car travels 20km/hr for 1.5h, 30km/hr for 2.0h, and at 40km/hr for 0.75 h. The car's average velocity is?

Define coefficient of thermal conductivity of a material. A cubical thermocole box of side 20 cm
and wall thickness 4 cm is full of ice. If outside temperature is 40 °C, estimate the amount of
ice melted in five hours (K for thermocol is 0.01 J s–1 °C–1 and latent heat of fusion of ice is 335 J
g–1)

Take a hollow plastic ball (dia 3 cm to 5 cm) using a needle. Pass a thread of about 105 cm along
a diameter of the ball. Tie a knot at one end. Hang the ball from a rigid support so that the ball is
free to oscillate. Make a small hole (5 mm dia) in the ball near the top. Fill it with sand and find its
time period of oscillation. Empty the ball and fill it with steel balls/iron filings and repeat the
experiment. Similarly carry out the experiment with common salt. Compare the time periods
obtained in the above three cases. What do you find? Explain your finding.

Define molar specific heat of a gas at constant volume (CV) and constant pressure (Cp). Obtain the
ratio Cp/Cv for a hydrogen gas using the law of equipartition of energy.