How can you demonstrate that charged objects exert forces, both attractive and repulsive

Alana is skateboarding at 19 km/h and throws a tennis ball at 11 km/h to her friend Oliver who is behind her leaning against a wall.

If a spring constant is 40 N/m and an object hanging from it stretches it 0.50 m, what is the mass of the object?

This includes all the means for communicating information to the general public. a. wire services c. newspapers b. mass media d. telecommunications

A train is moving at a constant speed on a surface inclined upward at 15.0° with the horizontal and travels 300 meters in 5 seconds. Calculate the horizontal velocity of the train at the end of 3 seconds.

A box of mass?=21.0 kgm=21.0 kg is pulled up a ramp that is inclined at an angle?=21.0∘θ=21.0∘ angle with respect to the horizontal. The coefficient of kinetic friction between the box and the ramp is? k=0.285μk=0.

Why do you float in space

How does physical change affect the identity of a substance

A scientist pours grape juice on three identical white shirts He then uses three different cleaning products on the shirts and measures how clean they get what is the independent variable in this experiment

What part of the atom does nuclear radiation come from?

Why should scientists write reports and give oral presentations of the steps and results of their in investigations?