Answering the two questions in reverse order:
-- No. I don't need to know how the speed of the person changed before I can answer the question. I can answer it now.
-- The NET work done by the gravitational force is<em> zero</em>.
-- As the person and his girl-friend go up the first half of the wheel, the motor does positive work and gravity does negative work.
-- After they pass the peak at the top and come down the second half of the wheel, the motor does negative work and gravity does positive work, even though the couple may be interested in other things during that time.
-- The total work done by gravity in one complete revolution is zero.
-- The total work done by the motor in one complete revolution is only what it takes to pay back the energy robbed by friction and air resistance.
Answer:
Explanation:
given,
mass of the weight = 8 Kg
distance = 0.55 m
angle below horizontal = 30°
torque about shoulder
torque about his shoulder join is equal to
Answer:
The correct option is;
B) No, the Navy vessel is slower
Explanation:
The speed of some torpedoes can be as high as 370 km/h. The average speed of a fast Navy vessel is approximately 110 km/h
Therefore, the torpedoes travel approximately 3 times as fast as the (slower) Navy vessel, such that the torpedo covers three times the distance of the Navy vessel in the same time and therefore, if the Navy vessel and the torpedo continue in a straight line (in the same direction) due north the vessel can not outrun the torpedo
Therefore, no the Navy vessel travels slower than a torpedo.
Answer:
Explanation:
<u>Motion With Constant Acceleration
</u>
It's a type of motion in which the velocity of an object changes uniformly over time.
The equation that describes the change of velocities is:
Where:
a = acceleration
vo = initial speed
vf = final speed
t = time
Solving the equation for a:
The ball starts at rest (vo=0) and rolls down an inclined plane that makes it reach a speed of vf=7.5 m/s in t=3 seconds.
The acceleration is:
Answer:
Explanation:
Given data:
Let the distance traveled by the object in the second case be 
In the given problem, work done by the forces are same in both the cases.
Thus,
