4. A steel cable spanning a river is 220.000 m long when the temperature is 30.°C.
What will be its length when the temperature drops to 0°C? (The coefficient of
thermal expansion of steel is 12x10-6K-1).

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Agroup of students were investigating the force of gravity. they began by dropping a foam ball from a height of 3 meters into a bucket of sand. the ball hit the sand in 0.306 seconds. they dropped additional balls of approximately the same diameter, but of different masses. here is the data they collected. based on this experiment and the collected data, what would their conclusion be?

Two point charges are on the y axis. a 3.90-µc charge is located at y = 1.25 cm, and a -2.4-µc charge is located at y = −1.80 cm. (a) find the total electric potential at the origin. v (b) find the total electric potential at the point whose coordinates are (1.50 cm, 0). v