Answer:
The work done on the athlete is approximately 2.09 J
Explanation:
From the definition of the work done by a variable force:

and substituting with the function of our problem:

Answer:

Explanation:
Project mass m=3.8 kg
Initial speed vi= 0m/s
Final speed vf= 9.3×10³ m/s
Force F=9.3×10⁵N
To find
Time t
Solution
From Newtons second law we know that
∑F=ma
Where m is mass
a is acceleration
We can write this equation as
∑F=m(Δv/Δt)

Rearrange this equation to find time t
So

Substitute the given values
Answer:
5 kg
Explanation:
Acceleration = 6 m/s^2
Force = 30 N
Force = mass * acceleration
mass = force / acceleration
mass = 30 / 6
mass = 5 kg
The work is path independent since we have a conservative force.
Thus
Answer (1)
Answer:
15.07 ksi
Explanation:
Given that:
Pitch (P) = 5 teeth/in
Pressure angle (
) = 20°
Pinion speed (
) = 2000 rev/min
Power (H) = 30 hp
Teeth on gear (
) = 50
Teeth on pinion (
) = 20
Face width (F) = 1 in
Let us first determine the diameter (d) of the pinion.
Diameter (d) =
=
= 4 in
From the values of Lewis Form Factor Y for (
) = 20 ; at 20°
Y = 0.321
To find the velocity (V); we use the formula:


V = 2094.40 ft/min
For cut or milled profile; the velocity factor
can be determined as follows:


= 2.0472
However, there is need to get the value of the tangential load
, in order to achieve that, we have the following expression




Finally, the bending stress is calculated via the formula:



15.07 ksi
∴ The estimate of the bending stress = 15.07 ksi