The work done on the barbell is -165.62 Nm.
Explanation:
Work done on any object is the measure of force required to move that object from one position to another. So it is determined by the product of force acting on the object with the displacement of the object.
In the present problem, the displacement of the object on acting of force is given as 1.3 m. And the weight of the object which is a barbel is given as 13 kg. As the work is to lift the object from the ground, so the acceleration due to gravity will be acting on the object. In other words, the force applied on the object to lift it should be in opposite direction to the acting of acceleration due to gravity.
Thus, 
Now, the force is -127.4 N and the displacement is 1.3 m.
So, 

So, the work done on the barbell is -165.62 Nm.
Thank you for posting your question here at brainly. I hope the answer will help. Below are the choices that can be found elsewhere:
<span>A. 1.5 * 10^3 Watts
B. 7.3 * 10^2 Watts
C. 3.5 * 10^2 Watts
D. 2.5 * 10^2 Watts
</span>
<span>Work = force*displacement = 10^2*87 = 8,700 joule
Power = work/time = 8,700/6 = 1.45*10^3 (rounded up to 1.5 kw). The answer is A. </span>
Answer:
455165.278 m
Explanation:
P = Power = 3.7 W
v = Velocity = 10.7 m/s
Amount of fat = 4 g
1 gram of fat provides about 9.40 (food) Calories
Energy given by 4 g of fat

Time required to burn the fat

Distance traveled by the bird

The bird will fly 455165.278 m
Answer:195 J
Explanation:
Given
mass of ball 
ball leaves the hand with 
maximum height reached by ball 
Initial Mechanical energy when ball just leaves the hand


considering hand to be datum so h_1=0[/tex]
so Potential energy at ground is zero


Mechanical Energy at highest point

at highest Point velocity is zero



Decrease in Mechanical energy


Answer:

Explanation:
To solve this problem we use the Momentum's conservation Law, before and after the girl catch the ball:
(1)
At the beginning the girl is stationary:
(2)
If the girl catch the ball, both have the same speed:
(3)
We replace (2) and (3) in (1):

We can now solve the equation for v_{f}:
