Answer:
Explanation:
From the question, we can see that the elevator is at a constant speed, invariably, acceleration is zero. And thus, there is no external force acting in the man, asides from force of gravitation acting on the man between those 5s. Now, we solve the question using newton's second law of motion.
The second law of motion states that, "the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object."
Summation Fy = ma(y)
F(n) - F(g) = 0
F(n) - mg = 0
F(n) = mg
F(n) = 77*9.81
F(n) = 755.37N
Answer
1400 * 0.8 = 1,120
the useful energy output is 1,120 joules
Using sources that are peer reviewed
Answer:
Note: Angular momentum is always conserved in a collision.
The initial angular momentum of the system is
L = ( It ) ( ωi )
where It = moment of inertia of the rotating circular disc,
ωi = angular velocity of the rotating circular disc
The final angular momentum is
L = ( It + Ir ) ( ωf )
where ωf is the final angular velocity of the system.
Since the two angular momenta are equal, we see that
( It ) ( ωi ) = ( It + Ir ) ( ωf )
so making ωf the subject of the formula
ωf = [ ( It ) / ( It + Ir ) ] ωi
Explanation: