Answer:D
Explanation:
It was right o khan academy
Answer:
Explained below
Explanation:
To explain this, let's consider a tennis ball being launched from the top of a very high building.
Now, if the tennis ball is launched horizontally without any upward angle but with an initial velocity of 10 m/s. In this motion, If there is no gravity, the tennis ball would continue in motion at that same speed of 10 m/s in the horizontal direction. However, in reality, gravity causes the tennis ball to accelerate downwards at a rate of 9.8 m/s for every second. This implies that the vertical velocity component is changing at the rate of 9.8 m/s every second.
Thus, after 1 second, horizontal velocity component will remain 10 m/s and vertical component will be 9.8 m/s × 1 = 9.8 m/s downwards.
Also, after 2 seconds, the vertical velocity component will remain 10 m/s, however the vertical component will now be 9.8 × 2 = 19.6 m/s downwards.
Same procedure is repeated as t increases by 1 second.
Answer:
<em>0.97c</em>
<em></em>
Explanation:
From the relativistic equation for length contraction, we have
= 
where
is the final length of the object
is the original length of the object before contraction
β = 
where v is the speed of the object
c is the speed of light in free space = 3 x 10^8 m/s
The equation can be re-written as
/
= 
For the length to contract to one-fourth of the proper length, then
/
= 1/4
substituting into the equation, we'll have
1/4 = 
substituting for β, we'll have
1/4 = 
squaring both side of the equation, we'll have
1/16 = 1 - 
= 1 - 1/16
= 15/16
square root both sides of the equation, we have
v/c = 0.968
v = <em>0.97c</em>
Answer:
I think D
Explanation:
if energy is added,it wont stay the same,I beleive D is the only one that makes since,sorry if wrong