Answer:
Explanation:
Check attachment for solution
Answer:
Yes
Explanation:
There was a force, 500 lb.
and a motion in the direction of the force, in this case a negative direction.
Therefore the lifter did negative work on the mass of the barbell against gravity.
Gravity would do positive work against the mass of weight when the lifter lowers the barbell as the force vector and the motion vector are in the same direction.
In order to calculate the weight, we may simply use:
W = mg
W = 30 * 9.81
W = 294.3 N
The sum of the reaction force and the upward component of child pulling will be equal to total downward force. The force acting downwards is the weight. Therefore:
R + 12sin(45) = 294.3
R = 285.82 N
The acceleration can be found using the resultant force and the mass of the sled. The resultant force is:
F(r) = pulling force + pushing force - friction
F(r) = 12cos(45) + 8 - 5
F(r) = 11.48 N
a = F/m
a = 11.48 / 30
a = 0.38 m/s²
Answer:
the answer is c i know it
Explanation:
its c
Answer:
(a) T=6.07s
(b) 
Explanation:
For Part (a)
The initial amplitude is given as A=7.0 cm
Apply the equation 
with 
we have:
For Part (b)
Apply with t=4.0s and T=6.07s we have
