Answer: c
Explanation: it is c because i used my brain to answer it
Answer:
One way to test the hypothesis is to create two waves, one in the air and one on the ground at the same time. One of them for the elephant to get closer and another for the elephants to move away. Observe the reaction of the animal and with this we know which sound came first.
Explanation:
This hypothesis is based on the fact that the speed of sound in air is v = 343 m / s with a small variation with temperature.
The speed of sound in solid soil is an average of the speed of its constituent media, giving values between
wood 3900 m / s
concrete 4000 m / s
fabrics 1540 m / s
earth 5000 m / s wave S
ground 7000 m / s P wave
we can see that the speed on solid earth is an order of magnitude greater than in air.
One way to test the hypothesis is to create two waves, one in the air and one on the ground at the same time. One of them for the elephant to get closer and another for the elephants to move away. Observe the reaction of the animal and with this we know which sound came first.
From the initial information, the wave going through the ground should arrive first.
Answer:
77%
Explanation:
efficiency= work output/work input X 100%
e = 1,200j/ 1,550 j x100%
e = 1,200/1,550= 0.77
e = 0.77 x 100%
e = 77%
Answer:
Explanation:
Remark
The only thing that might trip you up is what to do with the angle. The vertical component of the 15 degrees does no work against anything. So the 15 degrees limits the horizontal force.
The formula is
Work = F * d * cos(15)
The givens are
F = 2000 N
d = 30 m
Cos(15) = 0.9659
Solution
Work = 2000 * 30 * cos(15)
Work = 57,955
Rounded to two places would be 5.8 * 10^4
C
