The answer to this question is A - 25 N
Answer:
22 degree
Explanation:
Angle of incidence, i = 30 degree
the refractive index of water with respect to air is 4/3.
As the ray of light travels from rarer medium to denser medium, that mean air to water, the refraction takes place.
According to Snell's law,
Refractive index of water with respect to air = Sin i / Sin r
Where, r be the angle of refraction
4 / 3 = Sin 30 / Sin r
0.75 = 2 Sin r
Sin r = 0.375
r = 22 degree
Thus, the angle of refraction is 22 degree.
Answer:
Greater than
Explanation:
The Wavelength will be higher than what will be heard without any motion on the boat due to the Doppler Effect, which is the change in the frequency of a sound wave whenever there's a relative motion between the source of the wave and observer. The amount of shift in frequency depends on the speed of the source towards the observer; the higher the velocity of the source, the higher the shift.
Answer:
660 centimeters
Explanation:
There are 100 cm in 1 m. To convert from m to cm, multiply by 100.
There are 660 cm in 1 m.
Answer:
Time = 0.55 s
Height = 8.3 m
Explanation:
The ball is dropped and therefore has an initial velocity of 0. Its acceleration, g, is directed downward in the same direction as its displacement, 
.
The dart is thrown up in which case acceleration, g, acts downward in an opposite direction to its displacement, 
. Both collide after travelling for a time period, t. Let the height of the dart from the ground at collision be and the distance travelled by the ball measured from the top be .
It follows that 
.
Applying the equation of motion to each body (h = v_0t + 0.5at^2),
Ball:
(since 
.)
Dart:
(the acceleration is opposite to the displacement, hence the negative sign)
But
The height of the collision is the height of the dart above the ground, .
