Answer:
a= - 6.667 m/s²
Explanation:
Given that
The initial speed of the box ,u= 20 m/s
The final speed of the box ,v= 0 m/s
The distance cover by box ,s= 30 m
Lets take the acceleration of the box = a
We know that
v²= u ² + 2 a s
Now by putting the values in the above equation we get
0²=20² + 2 a x 30
a= - 6.667 m/s²
Negative sign indicates that velocity and acceleration are in opposite direction.
Therefore the acceleration of the box will be - 6.667 m/s² .
(a) At a corresponding hill on Earth and a lesser gravity on planet Epslion, the height of the hill will cause a reduction in the initial speed of the snowboarder from 4 m/s to a value greater than zero (0).
(b) If the initial speed at the bottom of the hill is 5 m/s, the final speed at the top of the hill be greater than 3 m/s.
<h3>
Conservation of mechanical energy</h3>
The effect of height and gravity on speed on the given planet Epislon is determined by applying the principle of conservation of mechanical energy as shown below;
ΔK.E = ΔP.E
¹/₂m(v²- u²) = mg(hi - hf)
¹/₂(v²- u²) = g(0 - hf)
v² - u² = -2ghf
v² = u² - 2ghf
where;
- v is the final velocity at upper level
- u is the initial velocity
- hf is final height
- g is acceleration due to gravity
when u² = 2gh, then v² = 0,
when gravity reduces, u² > 2gh, and v² > 0
Thus, at a corresponding hill on Earth and a lesser gravity on planet Epslion, the height of the hill will cause a reduction in the initial speed of the snowboarder from 4 m/s to a value greater than zero (0).
<h3>Final speed</h3>
v² = u² - 2ghf
where;
- u is the initial speed = 5 m/s
- g is acceleration due to gravity and its less than 9.8 m/s²
- v is final speed
- hf is equal height
Since g on Epislon is less than 9.8 m/s² of Earth;
5² - 2ghf > 3 m/s
Thus, if the initial speed at the bottom of the hill is 5 m/s, the final speed at the top of the hill be greater than 3 m/s.
Learn more about conservation of mechanical energy here: brainly.com/question/6852965
Answer:
Given values of Planck Constant are equivalent in English system and metric system.
Explanation:
Value of Planck's constant is given in English system as 4.14 x 10⁻¹⁵eV s.
Converting this in to metric system .
We have 1 eV = 1.6 x 10⁻¹⁹ J
Converting
4.14 x 10⁻¹⁵eV s = 4.14 x 10⁻¹⁵x 1.6 x 10⁻¹⁹ = 6.63 x 10⁻³⁴ Joule s
So Given values of Planck Constant are equivalent in English system and metric system.
The actual question should be did the sound waves escape room?
Yes they can escape the room
- Sound always needs a medium to travel through
- If you close the room form all where that even air can't go outside you will be able to hear no sound coming from room .
