Answer:
The value of capillary rise in the tube = 0.0363 cm
Explanation:
Diameter of the glass tube = 0.03 meter
Contact angle = 22 degree
We know that the capillary rise (h) in the tube is given by the formula =
h = (2 α cos β) / (d g R )
⇒ d = density of gasoline = 749 kg / 
β = 22 degree
R = radius of the tube = 0.015 m
α = surface tension of gasoline = 0.0216 N / m
cos 22 = 0.927
Put all the values in the above formula we get
⇒ h = (2 × 0.0216 × 0.927) / (749 × 9.81 × 0.015)
⇒ h = 0.0363 cm
This is the value of capillary rise in the tube.
Answer:
24°
Explanation:
sin(34°)/sin(x)=v2/v1
x=arcsin(2,1*sin(34°)/2,8)=24°
Answer is D.
Speed:
Use relative speed to simplify the situation. Since the trains are moving in opposite directions, you can add the speeds and pretend the first train is stationary (moving at 0m/s) and the second train is moving at 50m/s.
Distance:
The front of the second train needs to travel 120m to get from the front to the back of the first train. When the front of the second train is at the back of the first train, the back of the second train is still 10m in front of the first train. The back therefore has to travel 130m to clear the first train. The total distance over which the trains are overlapping in this scenario is therefore 120 + 130 = 250m.
You have speed and you have distance so now just calculate time:
v = d / t
50 = 250 / t
t = 5s
Axis labels. We don’t know what is being compared with the data
The ball's horizontal and vertical velocities at time 
are
but the ball is thrown horizontally, so 
. Its horizontal and vertical positions at time are
The ball travels 22 m horizontally from where it was thrown, so
from which we find the time it takes for the ball to land on the ground is
When it lands, 
and
