We use 1/o + 1/i = 1/f where o is the distance of the object, i as distance of the image and f is the focal length.
Substituting, <span>1/ 100 + 1 / i = - 1 /25 </span>
<span>i = - 20 cm </span>
<span>For the case of the problem,</span>
<span>o = (20 + 30) = 50 cm </span>
<span>f = 33.33. </span>Using 1<span> / i + 1 / o = 1/f , </span><span> </span><span>i = 100 cm </span>
<span>M = magnification = - i / o </span>
<span>m1 = -(-20)/100 = 20/100 = 0.2 </span>
<span>m2 = -100/50 = -2 </span>
<span>M = m1*m2 = -2 x 0.2 = -0.4.</span>
The speed of sound is influenced by several factors, including medium, density and temperature. The rate at which sound waves moves varies widely from one situation to the next and can change dramatically in a short period of time.
Answer:
a) 27.2 rad/min
b) 260 rev/h
Explanation:
The passenger is traveling at 9 mph, this is the tangential speed.
The relation between tangential speed and angular speed is:
v = r * w
Where
v: tangential speed
r: radius
w: angular speed
Also, the radius is
r = d/2
d is the diameter
Therefore:
v = (d * w)/2
Rearranging:
w = 2*v/d
w = (2*9 mile/h)/(58 feet)
We need to convert the feet to miles
w = (2*9 mile/h)/(0.011 miles) = 1636 rad/h
We divide this by 60 to get it in radians per minute
w = 1636/60 = 27.2 rad/min
Now the angular speed is in radians, to get revolutions we have to divide by 2π
n = v/(π*d)
n = (9 mile/h)/(π*0.011 mile) = 260 rev/h
Displacement is distance moved,so if you have your velocity in m/s you need your total time in seconds and multiply the two to get displacement so at 1.2m/s travelling (9.5*60(60seconds in a minute)=570 seconds is 570*1.2=684
The forces the people exert on the plank is 100.45N
<u>Explanation:</u>
Force of man 1 on plank =
Force of man 2 on plank =
Gravitational force on plank =
Gravitational force on box =
Given hint is forces of people is equal to forces on plank and box
in the state of equilibrium normal force is equal and opposite to gravitational force.