A skydiver of mass 75 kg first falls freely without a parachute, then opens the parachute. Before the parachute opens, the skydiver’s terminal velocity is 60 m/s. After the parachute opens, the new terminal velocity is reduced to 15 m/s. Which statement best explains this change?
A satellite orbits Planet X at a constant speed in a circular path. The gravitational force provides the centripetal force needed for the orbit. The orbital speed v is related to the planet's mass M and orbital radius r by the formula v = √(G M / r), where G is the gravitational constant. If the mass of Planet X is doubled, while the orbital radius of the satellite remains the same, how must the orbital speed of the satellite change to maintain a stable orbit?
An object of mass 5 kg is placed on Earth where g = 10 N/kg. What is its weight?
A rocket is accelerating upwards away from Earth. According to Newton's Third Law, the force that propels the rocket forward is a reaction to which of the following?
Which of the following is a non-contact force?
Two blocks of masses 6 kg and 4 kg are connected by a light inextensible string over a smooth pulley. The 6 kg block is on a smooth horizontal table, and the 4 kg block hangs freely. What is the tension in the string when the system is released?