The last choice is your answer, I just did it.
Answer:
The length of the bridge during the hottest part of summer is
Explanation:
From the question we are told that
The length of the steel bridge is
The temperature for this length is
The temperature at summer
The coefficient of linear expansion is
Generally the change in length of the steel bridge is mathematically represented as
Substituting value
The length of the bridge in summer is mathematically evaluated as
Substituting values
Answer:
(a) 50 kJ
(b) 14.14 m/s
(c) 0 N
(d) 0 J
Solution:
As per the question:
Mass of car, m = 500 kg
Force, F = 1000 N
Distance traveled, s = 50 m
Now,
(a) The total work done can be given as:
(b) To calculate the speed of the car:
Using work-energy relation, we can say that the work done equals the change in the kinetic energy of the car:
where
v' = final velocity
v = initial velocity = 0
Now,
(c) To calculate the net force on the car when the velocity is constant:
The net force is given as the product of mass and acceleration:
F = ma
<em>Acceleration can be defined as the rate with which the velocity of the car changes and the since the velocity is constant, the car will not have any acceleration, a = 0</em>
Thus the net force is also zero.
(d) The total work done when the car moves with constant velocity:
You haven't told us what the passing percentage is on the exam,
or what the passing percentage is for the semester, or any of that.