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:
Mass of Little Sister = 44.17 kg
Explanation:
From Newton's second law of motion, the magnitude of force applied on the sled is given by the following formula:
F = ma
where,
F = Force Applied = 120 N
a = Acceleration = 2.3 m/s²
m = Mass of Sled + Mass of Little Sister = 8 kg + Mass of Little Sister
Therefore,
120 N = (2.3 m/s²)(8 kg + Mass of Little Sister)
(120 N)/(2.3 m/s²) = 8 kg + Mass of Little Sister
Mass of Little Sister = 52.17 kg - 8 kg
<u>Mass of Little Sister = 44.17 kg</u>
Answer:
33.725 rpm
Explanation:
The relationship between rotational speed in radians per second and acceleration is ...

We want the rotation rate in RPM, so we need the conversion ...

Then the required rotational speed in RPM is ...

The rotation rate needs to be about 33.7 rpm to give an acceleration of 1.4g at the astronaut's feet.
Answer:
1)
&
east of sign post
2)
east of sign post
3)
east of the signpost.
4) 
Explanation:
Given:
- position of motorcyclist on entering the city at the signpost,

- time of observation after being at x=5m east of the signpost,

- constant acceleration of the on entering the city,

- distance of the motorcyclist moments later after entering,

- velocity of the motorcyclist moments later after entering,

<u>Now the initial velocity on at the sign board:</u>

where:
initial velocity of entering the city at the signpost
Putting respective values:


1)
Position at time
sec.:
Using equation of motion,
because it has already covered 5m before that point

east of sign post
Velocity at time
sec.:



2)
Position when the velocity is
:
using equation of motion,


east of sign post
3)
Given that:
acceleration be, 
time, 
Position after the new acceleration and the new given time:
using equation of motion,


east of the signpost.
4)
now time of observation, 



I'm thinking that you're supposed to divide. So you would divide 5 into 60 and get 12