Answer:
Distance: 21 yd, displacement: 15 yd, gain in the play: 12 yd
Explanation:
The distance travelled by Sam is just the sum of the length of each part of Sam's motion, regardless of the direction. Initially, Sam run from the 3 yd line to the 15 yd line, so (15-3)=12 yd. Then, he run also 9 yd to the right. Therefore, the total distance is
d = 12 + 9 = 21 yd
The displacement instead is a vector connecting the starting point with the final point of the motion. Sam run first 12 yd straight ahead and then 9 yd to the right; these two motions are perpendicular to each other, so we can find the displacement simply by using Pythagorean's theorem:
Finally, the yards gained by Sam in the play are simply given by the distance covered along the forward-backward direction only. Since Sam only run from the 3 yd line to the 15 yd line along this direction, then the gain in this play was
d = 15 - 3 = 12 yd
Answer:
The torque about his shoulder is 34.3Nm.
The solution approach assumes that the weight of the boy's arm acts at the center of the boy's arm length 35cm from the shoulder.
Explanation:
The solution to the problem can be found in the attachment below.
Apply:
wavelength = speed/frequency
= 350 m/s : 140 Hz = 2.5 m.
Answer:
Explanation:
same idea as before Liam, first, find the parallel resistance in 35 || 20
(35*20) / (35+20) = 700 / 55 = 12.727272 ohms
now add the 12.727272 + 15 = 27.727272 ohms total resistance
V = IR
10 = I * 27.727272
10 / 27.727272 = I
0.360655 = I
V = IR (again, but across the 15 ohm resistor)
V = 0.360655 * 15
V = 5.4098
There are two different processes here:
1) we must add heat in order to bring the temperature of the water from
to
(the temperature at which the water evaporates)
2) other heat must be added to make the water evaporates
1) The heat needed for process 1) is
where
is the water mass
is the water specific heat
is the variation of temperature of the water
If we plug the numbers into the equation, we find
2) The heat needed for process 2) is
where
is the water mass
is the latent heat of evaporation of water
If we plug the numbers into the equation, we find
So, the total heat needed for the whole process is
