Explain why a balloon filled with air cannot float in the middle of a room without moving downwards but a helium balloon of the same size can?

When an electron is displaced in a semiconductor. the hole that's left behind

What are the benefits of the starter phase of a fitness program

The planet Pluto has 1/500 the mass and 1/15 the radius of Earth. What is the value of g on the surface of Pluto? (A) 0.3 m/s2 (B) 1.6 m/s2 (C) 2.4 m/s2 (D) 4.5 m/s2 (E) 7.1 m/s2

If a silver wire has a resistance of 4.50 ohms at 20.0 degrees Celsius, what is the temperature at which it will have 5.00 ohms resistance?

A race car starts from rest and speed up uniformly to the right until it reaches a maximum velocity of 60m/s in 15 sec

What occurs when an unstable atomic nucleus changes into other nuclei by emitting particles and energy

Can a simple machine's efficiency ever be greater than 100%? Explain your answer.

A fishbowl has a circular opening with a diameter of 13 cm. The fishbowl sits upright on a table in a magnetic field of 0.00110 T that is directed downward. What is the flux through the glass of the bowl? -1.5*10^-5 Wb -4.5*10^-4 Wb 0.0 Wb -5.

Why do cars need a cooling system in conjunction with the engine

A runner starts from rest and has an acceleration of 3 m/s2. How fast is she running after 1.1 seconds