Answer:
Explanation:
= v/f
^That is the formula we are going to use.
Now, we were given the speed (v), which is 20.
Now we need to find frequency, in order to solve for the wavelength.
Frequency is the amount of waves in a fixed unit of one second, meaning our F value is the value of 5 divided by 4.
5/4 = 1.25
Therefore our F is 1.25
Now lets plug it in
= v/f
= 20/1.25
= 16
Conversion:
= 8
The answer is 12.5 kg because 250N / 20m/s^2
I hope that helped
Answer: 6s
Explanation:
Vs=32m/s speed at beginning of slowing down
Vf=0m/s stop speed
a= -6 m/s² acceleration
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Use equation for acceleration :
a=(Vf-Vs)/t
a*t=Vf-Vs
t=(Vf-Vs)/a
t=(0-36)/-6
t=-36/-6
t=6 s
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!!
Heat released from combustion is calculated by multiplying the amount of substance being burned with its heat of combustion. From this, we can calculate the mass needed from the system above. The calculation is as follows:
-543 kJ = x x -1320 kJ/mol
x = 0.411 mol
Mass of x = 0.411 x 71.83 g/mol
Mass of x = 29.55 g