How much air must be pushed downward at 40.0 m/s to keep 800-kg helicopter aloft? a. 98.0 kg/s b. 196 kg/s c. 294 kg/s d. 392 kg/s
Correct option is b.) 196 kg/s
Calculations are given below

Hope this helps...
How much air must be pushed downward at 40.0 m/s to keep 800-kg helicopter aloft? a. 98.0...
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a race car of mass 37 kg is pushed with constant acceleration 10 m/s^2, how much force is applied on the race car if the kinetic friction coefficient is 0.5?
A helicopter is slowly accelerating straight upwards at a rate of 1.6 m/s². If the helicopter blades have to generate an upward force of 8400 N in order to cause this, then what must be the mass of the helicopter? (Take the acceleration of gravity g = 9.81 ) 92 * kg Now suppose the helicopter pilot reaches his desired speed, and no longer wants to accelerate (just maintain his upward velocity). How much force will the blades have to...
A meteoroid of mass = 595 kg has a speed of 79.0 m/s when 800 km
above the Earth. It is falling vertically (ignore air resistance)
and strikes a bed of sand in which it is brought to rest in 3.61
m.
(a) How much work does the force of gravity do on the meteoroid
on the way to the surface?
???? GJ
(b) What is the speed of the meteoroid just before striking the
sand?
???? m/s
(c) How...
A helicopter lifts a 76 kg astronaut 14 m vertically from the ocean by means of a cable. The acceleration of the astronaut is g/14. How much work is done on the astronaut by (a) the force from the helicopter and (b) the gravitational force on her? Just before she reaches the helicopter, what are her (c) kinetic energy and (d) speed?
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How much work is done by the rope to keep a ball of mass 1 kg in
uniform circular motion at speed 5 m/s?
How much work is done by the rope to keep a ball of mass 1 kg in uniform circular motion at speed 5 m/s? Answer:
A.) If each of the three rotor helicopter blades is
3.75
m
long and has a mass of 135
kg,
calculate the moment of inertia of the three rotor blades about the
axis of rotation.
B.)How
much torque must the motor apply to bring the blades from rest up
to a speed of 4.1
rev/s
in 7.6s
?
If each of the three rotor helicopter blades is 3.75 m long and has a mass of 135 kg, calculate the moment of...
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