Answer:
(a) 
Explanation:
We have given speed of light 
Given time = 1 year =365 days
We know that in 1 minute = 60 sec
1 hour = 60×60 = 3600 sec
In one day = 24 hour = 24×60×60=86400 sec
So in 365 days = 365×86400
We know that distance = speed ×time
We have given that 1 mi = 1609 m
So 
So option (a) is correct
Answer:
4) True. The change of direction needs an unbalanced force
Explanation:
Let us propose the resolution of the problem using Newton's second law.
F = m a
As the car is spinning the acceleration is centripetal
a = v2.r
F = m v2 / r
We can see that as the velocity of a vector even if its module does not change, the change of direction requires an external force.
Now we can analyze the statement if they are true or false
1) and 3) False, even when the speed changes, the direction changes
2) False with the speed change can be determined
4) True. The change of direction needs an unbalanced force
5) False are different things. the direction is where it is going and the speed is the magnitude of the vector
Answer:
1) a block going down a slope
2) a) W = ΔU + ΔK + ΔE, b) W = ΔE, c) W = ΔK, d) ΔU = ΔK
Explanation:
In this exercise you are asked to give an example of various types of systems
1) a system where work is transformed into internal energy is a system with friction, for example a block going down a slope in this case work is done during the descent, which is transformed in part kinetic energy, in part power energy and partly internal energy that is represented by an increase in the temperature of the block.
2)
a) rolling a ball uphill
In this case we have an increase in potential energy, if there is a change in speed, the kinetic energy also increases, if the change in speed is zero, there is no change in kinetic energy and there is a change in internal energy due to the stationary rec in the point of contact
W = ΔU + ΔK + ΔE
b) in this system work is transformed into internal energy
W = ΔE
c) There is no friction here, therefore the work is transformed into kinetic energy
W = ΔK
d) if you assume that there is no friction with the air, the potential energy is transformed into kinetic energy
ΔU = ΔK
Answer:
Explanation:
Let the magnitude of magnetic field be B .
flux passing through the coil's = area of coil x field x no of turns
Φ = 3.13 x 10⁻⁴ x B x 135 = 422.55 x 10⁻⁴ B .
emf induced = dΦ / dt , Φ is magnetic flux.
current i = dΦ /dt x 1/R
charge through the coil = ∫ i dt
= ∫ dΦ /dt x 1/R dt
= 1 / R ∫ dΦ
= Φ / R
Total resistance R = 61.1 + 44.4 = 105.5 ohm .
3.44 x 10⁻⁵ = 422.55 x 10⁻⁴ B / 105.5
B = 3.44 x 10⁻⁵ x 105.5 / 422.55 x 10⁻⁴
= .86 x 10⁻¹
= .086 T .
Answer:
Explanation:
<u>1. Name of the variables:</u>
<u>2. Formulae:</u>
<u>3. Solution (calculations)</u>
