Aclumsy astronaut falls into a crater on the moon. the crater is 13 meters deep. how long will the astronaut have before he hits the ground?

Aspecial electronic sensor is embedded in the seat of a car that takes riders around a circular loop-the-loop ride at an amusement park. the sensor measures the magnitude of the normal force that the seat exerts on a rider. the loop-the-loop ride is in the vertical plane and its radius is 23 m. sitting on the seat before the ride starts, a rider is level and stationary, and the electronic sensor reads 740 n. at the top of the loop, the rider is upside down and moving, and the sensor reads 370 n. what is the speed of the rider at the top of the loop?

What is the earliest point in the universe that we can observe? why can’t we see back further than this?

For waves in the ocean, the medium of the waves is a. air b. water c. energy d. a passing boat