Answer:
The time where the avergae speed equals the instaneous speed is T/2
Explanation:
The velocity of the car is:
v(t) = v0 + at
Where v0 is the initial speed and a is the constant acceleration.
Let's find the average speed. This is given integrating the velocity from 0 to T and dividing by T:
![v_{ave} = \frac{1}{T}\int\limits^T_0 {v(t)} \, dt](https://tex.z-dn.net/?f=v_%7Bave%7D%20%3D%20%5Cfrac%7B1%7D%7BT%7D%5Cint%5Climits%5ET_0%20%7Bv%28t%29%7D%20%5C%2C%20dt)
v_ave = v0+a(T/2)
We can esaily note that when <u><em>t=T/2</em></u><u><em> </em></u>
v(T/2)=v_ave
Now we want to know where the car should be, the osition of the car is:
![x(t) = x_A + v_0 t + \frac{1}{2}at^2](https://tex.z-dn.net/?f=x%28t%29%20%3D%20x_A%20%2B%20v_0%20t%20%2B%20%5Cfrac%7B1%7D%7B2%7Dat%5E2)
Where x_A is the position of point A. Therefore, the car will be at:
<u><em>x(T/2) = x_A + v_0 (T/2) + (1/8)aT^2</em></u>
v^2 = v0^2 +2ad
v^2 = 22^2 + 2*3.78*45 = 824.2
v= √824.2 = 28.7 m/s
Answer:
![q_2=2.47\times 10^{-4}\ C](https://tex.z-dn.net/?f=q_2%3D2.47%5Ctimes%2010%5E%7B-4%7D%5C%20C)
Explanation:
The charge on one object, ![q_1=9.9\times 10^{-5}\ C](https://tex.z-dn.net/?f=q_1%3D9.9%5Ctimes%2010%5E%7B-5%7D%5C%20C)
The distance between the charges, r = 0.22 m
The force between the charges, F = 4,550 N
Let q₂ is the charge on the other sphere. The electrostatic force between two charges is given by the formula as follows :
![F=\dfrac{kq_1q_2}{r^2}\\\\q_2=\dfrac{Fr^2}{kq_1}\\\\q_2=\dfrac{4550\times (0.22) ^2}{9\times 10^9\times 9.9\times 10^{-5}}\\\\q_2=2.47\times 10^{-4}\ C](https://tex.z-dn.net/?f=F%3D%5Cdfrac%7Bkq_1q_2%7D%7Br%5E2%7D%5C%5C%5C%5Cq_2%3D%5Cdfrac%7BFr%5E2%7D%7Bkq_1%7D%5C%5C%5C%5Cq_2%3D%5Cdfrac%7B4550%5Ctimes%20%280.22%29%20%5E2%7D%7B9%5Ctimes%2010%5E9%5Ctimes%209.9%5Ctimes%2010%5E%7B-5%7D%7D%5C%5C%5C%5Cq_2%3D2.47%5Ctimes%2010%5E%7B-4%7D%5C%20C)
So, the charge on the other sphere is
.
Answer:
Gamma radiation or Cathode rays
Explanation:
by striking incident gamma or cathode rays onto the solid when placed on a photographic plate
The farther apart the two objects, the weaker the gravitational attraction between them.