No, she has it backward. Waves interfere with each other and reflect off objects. When two waves overlap their amplitudes add. If they have the same sign this addition is constructive, meaning the amplitudes grow. If they have opposite signs this constitutes subtraction and the waves can partially, or completely cancel. This is known as interference. Reflection occurs when waves travel from one medium to another. If the wave impedance of the new medium is different (which it generally is) there will be a partial, or even total, reflection.
V ( initial ) = 20 m/s
h = 2.30 m
h = v y * t + g t ² / 2
d = v x * t
1 ) At α = 18°:
v y = 20 * sin 18° = 6.18 m/s
v x = 20 * cos 18° = 19.02 m/ s
2.30 = 6.18 t + 4.9 t²
4.9 t² + 6.18 t - 2.30 = 0
After solving the quadratic equation ( a = 4.9, b = 6.18, c = - 2.3 ):
t 1/2 = (- 6.18 +/- √( 6.18² - 4 * 4.9 * (-2.3)) ) / ( 2 * 4.9 )
t = 0.3 s
d 1 = 19.02 m/s * 0.3 s = 5.706 m
2 ) At α = 8°:
v y = 20* sin 8° = 2.78 m/s
v x = 20* cos 8° = 19.81 m/s
2.3 = 2.78 t + 4.9 t²
4.9 t² + 2.78 t - 2.3 = 0
t = 0.46 s
d 2 = 19.81 * 0.46 = 9.113 m
The distance is:
d 2 - d 1 = 9.113 m - 5.706 m = 3.407 m
GOOD LUCK AND HOPE IT HELPS U
Answer:
Yes
Explanation:
A body can possess velocity at the same time in horizontal and vertical direction
For example
A projectile
Answer:
a. The temperature of the copper changed more than the temperature of the water.
Explanation:
Because we're only considering the isolated system cube-water, the heat of the system should be constant, that implies the heat the cube loses is equal the heat the water gains (because by zero law of thermodynamics heat (Q) flows from hot body to cold body until reach thermal equilibrium and T1>T2). So:
(1)
But Q is related with mass (m), specific heat (c) and changes in temperature (
)in the next way:
(2)
Using (2) on (1):
Because we have an equality and 0.385 < 4.186 then 
to conserve the equality
I think that the girl has greater tangential acceleration because she is closer to the center and the acceleration is greater there.
