Answer:
V1 =8.1 m/s
Explanation:
height at highest point (h2) = 4.1 m
height at lowest point (h1) = 0.8 m
acceleration due to gravity (g) = 9.8 m/s^{2}
from conservation of energy, the total energy at the lowest point will be the same as the total energy at the highest point. therefore
mgh1 +
= mgh2 + 
where
- speed at highest point = V2
- speed at lowest point = V1
- mass of the girl and swing = m
- at the highest point, the speed is minimum (V1 = 0)
- at the lowest point the speed is maximum (V2 is the maximum speed)
- therefore the equation becomes mgh1 +
= mgh2
m(gh1 +
) = m(gh2)
gh1 +
= gh2
V1 = 
now we can substitute all required values into the equation above.
V1 = 
V1 = 
V1 =8.1 m/s
Kinetic energy than parked
Answer:
a) <em>8.33 x 10^-6 Pa</em>
b) <em>8.23 x 10^-11 atm</em>
c) <em>1.67 x 10^-5 Pa</em>
d) <em>1.65 x 10^-10 atm</em>
<em></em>
Explanation:
Intensity of the light
= 2500 W/m^2
speed of light
<u> </u>= 3 x 10^8 m/s
a) we know that the pressure for for a totally absorbing surface is given as
=
= 2500/(3 x 10^8) = <em>8.33 x 10^-6 Pa</em>
b) 1 atm = 101325 Pa
= (8.33 x 10^-6)/101325 = <em>8.23 x 10^-11 atm</em>
c) for a totally reflecting surface
=
= twice the value for totally absorbing
= 2 x 8.33 x 10^-6 = <em>1.67 x 10^-5 Pa</em>
d) 1 atm = 101325 Pa
= 2 x 8.23 x 10^-11 = <em>1.65 x 10^-10 atm</em>
Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.
Below is the solution:
<span>centripetal accel = 1.5*g
ω²r = 1.5*9.8m/s²
ω² * 8m = 14.7 m/s²
ω = 1.36 rad/s * 1rev/2πrads * 60s/min = 12.9 rpm</span>
Answer:
2.08 s
Explanation:
We are given that
Speed,v=50mph=73.3ft/s
1 mile=5280 feet
1 hour=3600 s
Distance,d=461 ft
t=2.5 s
v'=60 mph=88 ft/s
We have to find the perception reaction time.
Perception reaction distance=


