Answer:
I will suppose that: The initial velocity of the birdman is horizontal. Now, the only force acting on birdman will be the gravitational force, so we can write the acceleration of birdman as
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Explanation:
Answer:
0.446 mm
0.066 V/m
Explanation:
Given
We are given the length of the copper cable L = 3.30 km and the potential difference is V = 220 V
Solution
(a) We want to find the diameter d of the cable when the dissipated power is P = 50W. The power consumed by the cable depends on its resistance R and it is given by equation in the form
P= V^2/R (1)
Where V is the voltage in the cable. Now let us solve equation (1) for R and plug our values for V and P into equation (1) to get R
R = V^2/P = (220)^2/(50) = 968Ω
Now we can determine the diameter of the copper wire. The resistance R of the wires depends on the area of the wire, resistivity and the length of the cable. Where equation gives us the relationship between these variables in the form
R = pL/π*r^2 (solve for r)
r = √pL/πR (2)
Now we can plug our values for Rep and L into equation (2) to get the radius of the cable where p for copper equals 1.72 x 10-8 Ω m
r =√pL/πR
= √1.72 x 10-8 *3300m/968
= 0.234 mm
Therefore, the diameter is d= 2r = 2(0.234 mm) = 0.446 mm
(b) To determine the electric field we can use the values for the potential difference across the cable and the length of the cable, where the electric field is inversely proportional to the length of the cable as next
E =V/L
=220/3300m
= 0.066 V/m
The car's average <em>speed</em> is 97 km/hr.
Then for calculation purposes, we can assume that it covers 97 km in the
first hour, 97 km in the second hour, 97 km in the third hour, and 97 km in
the fourth hour.
All together, the car covers (97 x 4) = <em>388 km</em> of distance.
We don't know the car's velocity, because we have no information about the
<em>direction</em> it moved at any time during the four hours. So we have no way to
calculate how far it was from the starting point at the end of the fourth hour.
For all we can tell, if the direction (and therefore the velocity) varied just right,
the car could have ended up exactly where it started.
Answer:
The acceleration of the sled is 
.
Explanation:
It is given that,
Initial speed of sled is 0 because it was at rest.
It is placed at an angle of 28° on a frictionless hill.
We need to find the acceleration of the sled. It is placed at an incline. It means that the acceleration of the sled is given by :
So, the acceleration of the sled is .
Answer:
At its most natural frequency. ... A forceful voice, exquisite control of frequency, and oscillating
