Which term describes the amount of matter packed into a given space?

A. Heat

B. Temperature

C. Pressure

D. Density

at a particular instant a hot air balloon is 100m in the air and decending at a constant speed of 2m/s at this exact instant a girl throws a ball horizontally relative to herself with an initial speed of 20m/s when she lands where will she find the

Which of these is an indication that a chemical reaction has occurred? 1) melting of a substance 2) boiling of a substance 3) formation of a precipitate 4) freezing of a substance

The ramp on the back of a moving van is in example of what type simple machine

How does the gravitational force between two objects change if the distance between the objects is doubled? A. The gravitational force decreases by half. B. The gravitational force doubles. C. The gravitational force decreases by a factor of 4. D.

At what frequency does the driver of the car hear the ambulance's siren? The velocity of sound in air is 343 m/s.

As an airplane is taking off at an airport its position is closely monitored by radar. The following three positions are measured with their corresponding times: x1 = 241.22 m at t1 = 3.70 s, x2 = 297.60 m at t2 = 4.20 s, x3 = 360.23 m at t3 = 4.

A stunt car with a mass of 1000 kg crashes into a tree on a movie set during the collision acceleration of the car with 3 m what was the force of impact of the collision on the car

A circuit with a current of 400 amp has several lights that have a total resistance equal to 30 ohms. Find the voltage.

How many neutrons does element x have if it's atomic number is 35 and it's mass number 71

The potential difference between the terminal of an electrical heater is 60v when it draw a current 4A fron the source. What current will the heater draw if the potential difference is increased to 120v?