Answer: D.) 39,200 J
Via the equation of potential energy PE = mgh where m is mass, g is the average gravity on earth and h is the height. In this case m = 400 kg, g = 9.8, h = 10 m thus:
P.E.= 39,200 Joules
Lift force exerted by the air on the rotors=143244 N
Explanation:
we use Newtons second law
F- (M+m)g=(M+m)a
F= lift force
m= mass of helicopter= 13000 Kg
M= mass of car= 2000 lb=907.2 kg
a= acceleration= 0.5 m/s²
g= acceleration due to gravity
F- (M+m)g=(M+m)a
F=(M+m)(a+g)
F=(13000+907.2)(0.5+9.8)
F=143244 N
lf a heavy point mass is suspended by a weightless, inextensible and perfectly flexible string from a rigid support, then this arrangement is called simple pendulum.
In practice, however, these requirements cannot be fulfilled. So we use a practical pendulum.
A practical pendulum consists of a small metallic solid sphere suspended by a fine silk thread from a rigid support. This is the practical simple pendulum which is nearest to the ideal simple pendulum.
Note :
The metallic sphere is called the bob.
When the bob is displaced slightly to one side from its mean position and released, it oscillates about its mean position in a vertical plane.
<span>Ocean currents act much like a conveyer belt,
transporting warm water and precipitation from the equator toward the
poles and cold water from the poles back to the tropics. Thus, currents
regulate global climate, helping to counteract the uneven distribution of solar radiation reaching Earth's surface.</span>
Given that force is applied at an angle of 30 degree below the horizontal
So let say force applied if F
now its two components are given as
Now the normal force on the block is given as
now the friction force on the cart is given as
now if cart moves with constant speed then net force on cart must be zero
so now we have
so the force must be 199.2 N
