When the sum of all forces acting on a block on an inclined plane is zero, the block?

Why is chemical energy not accepted as a viable method for energy generation in the sun?

What do engineers need to ensure there is sufficient of when designing a roller coaster?

How do most primary producers make their own food?

Two children are playing with a roll of paper towels. One child holds the roll between the index fingers of her hands so that it is free to rotate, and the second child pulls at constant speed on the free end of the paper towels.

While John is traveling along a straight interstate highway, he notices that the mile marker reads 241 km. John travels until he reaches the 134 km marker and then retraces his path to the 167 km marker.

The theory describing the movement of the plates is called plate motion theory. True or false?

Would electromagnetic waves exist if changing magnetic fields could produce electric fields but changing electric fields could not, in turn, produce magnetic fields? Explain.

A person walks 4.0 kilometers north, then 4.0 kilometers west. His displacement is closest to

A radar station detects an airplane approaching directly from the east. at first observation, the range to the plane is d1 = 354 m at 40° above the horizon.

A bookshelf is 2m long, with supports at its end (p and q). A book weighing 10N is placed in the middle of the shelf. what are the upward forces?