22. a - (vf^2 - vi^2)/(2d)
a = (0 - 23^2)/(170)
a = -3.1 m/s^2
23. Find the time (t) to reach 33 m/s at 3 m/s^2
33-0/t = 3
33 = 3t
t = 11 sec to reach 33 m/s^2
Find the av velocuty: 33+0/2 = 16.5 m/s
Dist = 16.5 * 11 = 181.5 meters to each 33m/s speed. Runway has to be at least this long.
24. The sprinter starts from rest. The average acceleration is found from:
(Vf)^2 = (Vi)^2 = 2as ---> a = (Vf)^2 - (Vi)^2/2s = (11.5m/s)^2-0/2(15.0m) = 4.408m/s^2 estimated: 4.41m/s^2
The elapsed time is found by solving
Vf = Vi + at ----> t = vf-vi/a = 11.5m/s-0/4.408m/s^2 = 2.61s
25. Acceleration of car = v-u/t = 0ms^-1-21.0ms^-1/6.00s = -3.50ms^-2
S = v^2 - u^2/2a = (0ms^-1)^2-(21.0ms^-1)^2/2*-3.50ms^-2 = 63.0m
26. Assuming a constant deceleration of 7.00 m/s^2
final velocity, v = 0m/s
acceleration, a = -7.00m/s^2
displacement, s - 92m
Using v^2 = u^2 - 2as
0^2 - u^2 + 2 (-7.00) (92)
initial velocity, u = sqrt (1288) = 35.9 m/s
This is the speed pf the car just bore braking.
I hope this helps!!
Answer:
A) If the paintball stops completely the magnitude of the change in the paintball’s momentum is 
B) If the paintball bounces off its target and afterward moves in the opposite direction with the same speed, the change in the paintball’s momentum is 
C) A paintball bouncing off your skin in the opposite direction with the same speed hurts more than a paintball exploding upon your skin because of the strength exerted is twice than if it explodes.
Explanation:
Hi
A) We use the formula of momentum
, so we have 
B) We use the same formula above, then due we have a change of direction at the same speed, therefore the change in the momentum is the double so
.
C) The average strength of the force an object exerts during impact is determined by the amount the object’s momentum changes. therefore
, as we don't have any data about the impact time but we know momentum is twice, time does no matter and strength is twice too.
Answer:
The point at which the electrical potential is zero is x = +0.33 m.
Explanation:
By definition the electrical potential is:

Where:
K: is Coulomb's constant = 9x10⁹ N*m²/C²
q: is the charge
r: is the distance
The point at which the electrical potential is zero can be calculated as follows:

(1)
q₁ is the first charge = +3 mC
r₁ is the distance from the point to the first charge
q₂ is the first charge = -6 mC
r₂ is the distance from the point to the second charge
By replacing r₁ = 1 - r₂ into equation (1) we have:
(2)
By solving equation (2) for r₂:

Therefore, the point at which the electrical potential is zero is x = +0.33 m.
I hope it helps you!
Answer:
The intensity of light from the 1mm from the central maximu is 
Explanation:
From the question we are told that
The wavelength is 
The width of the slit is
The distance from the screen is 
The intensity at the central maximum is 
The distance from the central maximum is 
Let z be the the distance of a point with intensity I from central maximum
Then we can represent this intensity as
Now the relationship between D and z can be represented using the SOHCAHTOA rule i.e

if the angle between the the light at z and the central maximum is small
Then 
Which implies that

substituting this into the equation for the intensity
![I = I_o [\frac{sin [\frac{\pi w}{\lambda} \cdot \frac{z}{D} ]}{\frac{\pi w z}{\lambda D\frac{x}{y} } } ]](https://tex.z-dn.net/?f=I%20%3D%20I_o%20%5B%5Cfrac%7Bsin%20%5B%5Cfrac%7B%5Cpi%20w%7D%7B%5Clambda%7D%20%5Ccdot%20%5Cfrac%7Bz%7D%7BD%7D%20%20%5D%7D%7B%5Cfrac%7B%5Cpi%20w%20z%7D%7B%5Clambda%20D%5Cfrac%7Bx%7D%7By%7D%20%7D%20%7D%20%5D)
given that 
We have that
![I = I_o [\frac{sin[\frac{3.142 * 0.45*10^{-3}}{(620 *10^{-9})} \cdot \frac{1*10^{-3}}{3} ]}{\frac{3.142 * 0.45*10^{-3}*1*10^{-3} }{620*10^{-9} *3} } ]^2](https://tex.z-dn.net/?f=I%20%3D%20I_o%20%5B%5Cfrac%7Bsin%5B%5Cfrac%7B3.142%20%2A%200.45%2A10%5E%7B-3%7D%7D%7B%28620%20%2A10%5E%7B-9%7D%29%7D%20%5Ccdot%20%5Cfrac%7B1%2A10%5E%7B-3%7D%7D%7B3%7D%20%5D%7D%7B%5Cfrac%7B3.142%20%2A%200.45%2A10%5E%7B-3%7D%2A1%2A10%5E%7B-3%7D%20%7D%7B620%2A10%5E%7B-9%7D%20%2A3%7D%20%7D%20%5D%5E2)
![=I_o [\frac{sin(0.760)}{0.760}] ^2](https://tex.z-dn.net/?f=%3DI_o%20%5B%5Cfrac%7Bsin%280.760%29%7D%7B0.760%7D%5D%20%5E2)
