The evil Dr. L is involved in a plot to de-spin the Earth using knowledge acquired from the Franklin Institute. HE plans to mount a series of surplus rockets tangentially all along the equator. Taking the planet to be a uniform sphere of radius 6.37E6 m and mass 5.98E24 kg, how much continuous thrust would the rockets need to apply to accomplish the deed in 12 hours?

To travel at constant speed, a car engine provides 24kw of useful power. the driving force on the car is 600n. at what speed does it travel?

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

Aprojectile is launched from ground level with an initial velocity of v 0 feet per second. neglecting air resistance, its height in feet t seconds after launch is given by s equals negative 16 t squared plus v 0 t. find the time(s) that the projectile will (a) reach a height of 192 ft and (b) return to the ground when v 0equals112 feet per second. (a) find the time(s) that the projectile will reach a height of 192 ft when v 0equals112 feet per second. select the correct choice below and, if necessary, fill in the answer box to complete your choice.