How to find speed of a wave

A metal bar 70cm long and 4.00 kg in mass supported on two knief - edge placed 10 cm from each end. a 6.00 kg weight is suspended at 30 cm from one end. find the reaction at the knife-edge?

What is the current running through resistor five?

When a third object is brought in contact with the first object (after it gains the electrons), the resulting charge on the third object is 0.9 C. What was its initial charge (in C) ?

True or False? A model train traveling at a constant speed around a circular track has a constant velocity. (False) 2.

A 20 μF capacitor initially charged to 30 μC is discharged through a 1.5 kΩ resistor. Part A How long does it take to reduce the capacitor's charge to 10 μC? Express your answer with the appropriate units.

A 2.0-kilogram laboratory cart is sliding across a horizontal frictionless surface at a constant velocity of 4.0 meters per second east. What will be the cart's velocity after a 6.0-newton westward force acts on it for 2.

A boat floats with 25% of its volume under water. a. What is the boatâs density? b. If the boat was made from 500 kg of metal, what is the volume of the boat? (Assume the air in the boat has negligible mass and density) c.

Why does each mineral have their own property, different from every other mineral?

Earth's tallest mountain ranges are found at plate boundaries

Is a lung a living organism, why or why not?