Products made of plastic can last a very long time. Explain both the positive and negative effects of plastic being long-lasting.

If the gravitational forces exist between all objects in the universe why aren't people affected by the gravitational force exerted by cars and buildings?

What are supersonic speeds

How could the campfire warm things by conduction and radiation?

Two train carts are moving in the same direction, such that one cart catches up with and collides with the second cart. That is, a 480-kg train cart moving at 14.4 m/s hits from behind a 570-kg train cart that is moving at 13.

Asteroids were recently formed by the collision and breakup of an object orbiting in the asteriod belt. a. True b. False

A cricketer can throw a ball to a maximum horizontal distance of 100m. How much high above the ground can he throw same ball

What is the relationship between the slope of the position graph of an object and its velocity?

Differeniate between thermal energy and heat

The term that describes the time when the sun's are directly over the equator is:

A submarine can detect an approaching enemy submarine using sonar. If a stationary submerged submarine emits a 100kHz tone and receives a tone Doppler shifted by 200Hz, calculate the speed of the enemy submarine if the speed of sound in salt water