Answer:
According to the travellers, Alpha Centauri is <em>c) very slightly less than 4 light-years</em>
<em></em>
Explanation:
For a stationary observer, Alpha Centauri is 4 light-years away but for an observer who is travelling close to the speed of light, Alpha Centauri is <em>very slightly less than 4 light-years. </em>The following expression explains why:
v = d / t
where
- v is the speed of the spaceship
- d is the distance
- t is the time
Therefore,
d = v × t
d = (0.999 c)(4 light-years)
d = 3.996 light-years
This distance is<em> very slightly less than 4 light-years. </em>
Answer:
Maximum speed of the car is 17.37 m/s.
Explanation:
Given that,
Radius of the circular track, r = 79 m
The coefficient of friction, ![\mu=0.39](https://tex.z-dn.net/?f=%5Cmu%3D0.39)
To find,
The maximum speed of car.
Solution,
Let v is the maximum speed of the car at which it can safely travel. It can be calculated by balancing the centripetal force and the gravitational force acting on it as :
![v=\sqrt{\mu rg}](https://tex.z-dn.net/?f=v%3D%5Csqrt%7B%5Cmu%20rg%7D)
![v=\sqrt{0.39\times 79\times 9.8}](https://tex.z-dn.net/?f=v%3D%5Csqrt%7B0.39%5Ctimes%2079%5Ctimes%209.8%7D)
v = 17.37 m/s
So, the maximum speed of the car is 17.37 m/s.
Answer:
B. holding a coffee mug
Explanation:
Something must move a distance for work to be done.
Answer:
u have to purchase it via online e-commerce platforms