A race car driver must average 200km/hr for four laps to qualify for a race. Because of engine trouble, the car averages only 170km/hr over the first two laps. What is the average speed must be maintained for the last two laps

Projectile motion is a combination of which two types of motion?

What is surface tension? How does surface tension result from intermolecular forces? How is it related to the strength of intermolecular forces?

The pressure on a fluid is calculated as force/mass. True False

Which are properties of a liquid? Check all that apply. . can change shape to conform to a container . has a rigid shape that does not change easily . contains free-moving ions and electrons . is compressed more easily than other states .

Define ecosystem to show its scientific meaning

Why does a balloon filled with helium rise while a balloon filled with an equal volume of average atmospheric air does not? A. Helium has no mass, but air does. B. Helium increases the balloon's mass more than air. C.

Consider the following controls in an automobile in motion : gas pedal, brake, steering wheel. what are the controls in this list that cause an acceleration of the car?

What material are oil pipelines made from?

3/129 A 175-lb pole vaulter carrying a uniform 16-ft, 10-lb pole approaches the jump with a velocity v and manages to barely clear the bar set at a height of 18 ft. As he clears the bar, his velocity and that of the pole are essentially zero.

A few years ago, Serena Williams dived to hit a tennis ball right after it bounced off the ground. The ball bounced on the ground 10.3 m from the net, and after Serena hit the ball it flew over the 0.