When the Sun is slightly below the horizon, its light moves from less dense air to more dense air and gets refracted towards the normal. Because of this atmospheric refraction, the Sun appears to be above the horizon when it is actually slightly below the horizon.
Answer:
y = 1.06 x + 0.14
r² = 0.95
Explanation:
a) To make this graph, a spreadsheet-type calculation program is used, see attached.
On the y axis are the measured values
On the x-axis, the values checked in the experiment are placed.
From the graph we see that a linear graph and that one of the values has a strong deviation with respect to the others
b) The red line is the best straight line that can be drawn,
for this the quality ajust is r²
the closer to 1 the better the fit
the equation of the line is
y = 1.06 x + 0.14
r² = 0.95
Answer: 210.2N
Explanation:
Assume a bucket of water with a total mass of 68kg is attached to a rope, which in turn is tied around a 0.078m radius cylinder at the top of a well. A crank with a turning radius of 0.250 m is attached to the end of the cylinder.
the minimum force directed perpendicular to the crank handle required to raise the bucket is
(Assume the rope's mass is negligible, that the cylinder turns on friction-less bearings, and that g = 9.8 m/s2
The crank handle provides a torque T=0.25F where F is the force we are looking for.
A free body diagram will show that the tension in the rope times the cylinder radius R is equal to the torque on the cylinder. But the tension in the rope is just the weight of the bucket
W=mg= 68kg
W(0.078)=T=0.25F
F=0.312W=0.312(68kg)=21.216kg= 210.2N
