A block kept on a frictionless horizontal surface is acted upon by a force of 100N, as shown in the figure below. What magnitude of force must be applied on the block from the opposite direction to stop its motion?

A) 50 N
B) 75 N
C) 100 N
D) 200 N​

Waves that cause the most damage during an earthquake are a. surface waves c. s waves b. p waves d. ocean waves

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?