When the resistance decreases, the current increases.
Sue from Burkey and Keith from Baron will meet in 2 minutes
Answer: Option b
<u>Explanation:</u>
Time taken can be calculated when distance and the speeds are given. Here speeds of Keith and Sue are given. So, we have to find the relative speeds in order to calculate the time taken.
When two objects travel in same direction the relative speed will be the difference between speeds. Similarly when two objects travel in opposite direction, the relative speed will be the sum of given speeds.
Given:
Speed of Sue from Burkey is 6 km/hr and speed of Keith from Baron is 3 km/hr.
The distance between Burkey and Baron is 300 m.
From the formula,
where d is distance,s is speed and t is time
It can be derived that,
s = sum of given speeds = 3 km/hr + 6 km/hr = 9 km/hr
d = 300 m = 0.3 km
Answer:
B. Axial stress divided by axial strain
Explanation:
Elasticity:
It is the tendency of an object to deform along the axis when an opposing force is applied without facing permanent change in shape.
Plasticity:
When an object crosses the elasticity limit, it enters plasticity where the change due to stress is permanent and the object might even break.
Yield strength:
Yield strength is the point of maximum bearable stress that indicates the limit of elasticity.
Our case:
As the stress applied is less than the yield strength, the rod is still in the elasticity state and its modulus can be calculated.
Modulus of Elasticity = Stress along axis/Ratio of change in length to original length
Axial strain is basically the ratio of change in length to original length.
So, Modulus of Elasticity = Axial Stress/ Axial Strain
Answer:
W = 0 :The work done on the wall is zero,because the wall is not moving
Explanation:
Work theory
Work is the product of a force applied to a body and the displacement of the body in the direction of this force.
W= F*d Formula (1)
W: Work (Joules) (J)
F: force applied (N)
d=displacement of the body (m)
The work is positive (W+) if the force goes in the same direction of movement.
The work is negative (W-)if the force goes in the opposite direction to the movement
Data
F= 400-N
d= 0
Problem development
We apply formula (1) to calculate the work done on the wall:
W= 400*0
W=0
Answer:
9000RPM
Explanation:
"Angular velocity" is directly related to kinetic energy, that is, the Kinetic energy equation would allow an approximation to the resolution investigated in the problem.
The equation for KE is given by:
Now, starting from there towards the <em>Angular equation of kinetic energy</em>, the moment of inertia (i) is used instead of mass (m), and angular velocity (w) instead of linear velocity (V)
That's how we get
calculating the inertia for a solid cylindrical disk, of
m = 400kg
r = 1.2 / 2 = 0.6m
We understand that the total kinetic energy is 3.2 * 10 ^ 7J, like this:
Thus,
943 rad / s ≈ 9000 rpm