What is the speed of sound in air at 40°C?

Mrs. Brown's class is studying magnets and electricity. At the end of the unit Claire states that magnets and electricity are both non-contact forces like gravity, but they are not related other than that.

Consider a box weight 2700 newtons resting on the ground. If the area of the box touching the ground is 1.5 square meters, what pressure does the box exert on the ground?

A spring with an unknown force constant is compressed as shown. If the original length of the spring is 60cm, determine (a) the spring force constant (b) the compressive stress in the spring (c) the strain of the spring

A horizontal air diffuser operates with inlet velocity and specific enthalpy of 250 m/s and 270.11 kj/kg, repectively, and exit specific enthalpy of 297.31 kj/kg.

A loaded ore car has a mass of 950 kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at 34.0° above the horizontal.

Claudia throws a baseball to her dog. Which free-body diagram shows the baseball when it's flying horizontally in midair? (Assume no air resistance.)

What causes an air conditioned to turn on

A turntable is spinning on a frictionless axle when a ball of putty is dropped onto it from above. The putty sticks to the turntable when it lands. Is angular momentum conserved for the turntable and putty (the system) during this process?

The speedof a boat in still water is v. The boat is to make a round-trip ina river whose current travels at speed u.

Why are there so few working wave power stations?