The sound waves travel because of the pitch of the note so the window rattles.
Answer:
<em>I must travel with a speed of 2.97 x 10^8 m/s</em>
Explanation:
Sine the spacecraft flies at the same speed in the to and fro distance of the journey, then the time taken will be 6 months plus 6 months
Time that elapses on the spacecraft = 1 year
On earth the people have advanced 120 yrs
According to relativity, the time contraction on the spacecraft is gotten from
= 
where
is the time that elapses on the spacecraft = 120 years
= time here on Earth = 1 year
is the ratio v/c
where
v is the speed of the spacecraft = ?
c is the speed of light = 3 x 10^8 m/s
substituting values, we have
120 = 1/
squaring both sides of the equation, we have
14400 = 1/
14400 - 14400
= 1
14400 - 1 = 14400
14399 = 14400
= 14399/14400 = 0.99
= 0.99
substitute β = v/c
v/c = 0.99
but c = 3 x 10^8 m/s
v = 0.99c = 0.99 x 3 x 10^8 = <em>2.97 x 10^8 m/s</em>
Answer:
3g/cm³
Explanation:
<em>Use the formula:</em>
density = mass ÷ volume
<em>Substitute (plug in) the values:</em>
density = 3 ÷ 1 = 3g/cm³
Answer:
1500000 Pa
Explanation:
The formula for pressure is force per unit area.
P=F/A where F is force and A is area
Given that ;
F= mass * acceleration due to gravity
F= 60 * 9.81 = 588.6 = 589 N
A= area = 4cm² = 0.0004 m²
P= F/A = 589 / 0.0004
P= 1471500
P=1500000 Pa
This phenomena is also called the Doppler shift. When the source of light is approaching towards an observer, the color tends to be blue shifted, but when the source is moving away or being stretch, the color tends to red shifted. In astronomy it can be use how fast galaxy is moving towards us or how fast it moves away.