3 is false 2 is true and the rest true
He needs to improve his endurance time.
Answer:
a. P.E = 3430Joules.
b. Workdone = 3430Nm
Explanation:
<u>Given the following data;</u>
Mass = 70kg
Distance = 5m
We know that acceleration due to gravity is equal to 9.8m/s²
To find the potential energy;
Potential energy = mgh
P.E = 70*9.8*5
<em>P.E = 3430J</em>
b. To find the workdone;
Workdone = force * distance
But force = mass * acceleration
Force = 70*9.8
Force = 686 Newton.
Workdone = 686 * 5
<em>Workdone = 3430Nm</em>
First, we determine the volume of the trunk by finding
first the radius from the circumference through the equation,
<span> C
= 2πr</span>
<span> r
= C/2π</span>
Substituting the known values,
<span> r
= 4.5/2π = 0.716 m</span>
Then, we calculate for the volume through the equation,
<span> V
= πr2h</span>
<span> V
= π(0.716 m)2(8m) = 12.9 m3</span>
Multiplying the calculated value to the density will give
the mass as,
<span> Mass
= (12.9 m3)(752 kg/m3) = <span>9699.36 kg</span></span>