Answer:
8 signals received by twin A during the trip.
Explanation:
Given that,
Distance = 12 light year
Speed = 0.6 c
Time = 1 year
We need to calculate the time by A
Using formula of time
Put the value into the formula
Similarly,
The expression for distance cover by A
We need to calculate the time
Using formula of time
We need to calculate the signals received by twin A
Using formula for number of signals
Put the value into the formula
Hence, 8 signals received by twin A during the trip.
Answer:
The the speed of the car is 26.91 m/s.
Explanation:
Given that,
distance d = 88 m
Kinetic friction = 0.42
We need to calculate the the speed of the car
Using the work-energy principle
work done = change in kinetic energy
Put the value into the formula
Hence, The the speed of the car is 26.91 m/s.
Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
-
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
-
)
= 0.2(
)
f = = 150
For air (nair = 1):
= (1.5 - 1)(
-
)
f = = 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.