Answer:
After 1 sec = 4.9 m
After 2 sec = 19.6 m
After 3 sec = 44.1 m
After 4 sec = 78.4 m
After 5 sec = 122.5 m
Explanation:
After 1 sec:
<em>u=0m/s t=1 s a=9.8m/s²</em>
s = ut + (1/2)at²
=0(1) + (1/2)(9.8)(1²) = 4.9m
After 2 sec:
<em>u=0m/s t=2 s a=9.8m/s²</em>
s = ut + (1/2)at²
=0(2) + (1/2)(9.8)(2²) = 19.6m
After 3 sec:
<em>u=0m/s t=3 s a=9.8m/s²</em>
s = ut + (1/2)at²
=0(3) + (1/2)(9.8)(3²) = 44.1m
After 4 sec:
<em>u=0m/s t=4 s a=9.8m/s²</em>
s = ut + (1/2)at²
=0(4) + (1/2)(9.8)(4²) = 78.4m
After 5 sec:
<em>u=0m/s t=5 s a=9.8m/s²</em>
s = ut + (1/2)at²
=0(5) + (1/2)(9.8)(5²) = 122.5m
Answer:
Explanation:
Given:
- wavelength of light in the air,
- time taken to travel from the source to the photocell via air,
- time taken to reach the photocell via air and glass slab,
- thickness of the glass slab,
<u>Now we have the relation for time:</u>
hence,
c= speed of light in air
For the case when glass slab is inserted between the path of light:
(since light travel with the speed c only in the air)
here:
v = speed of light in the glass
Using Snell's law:
I believe the answer is A) Less work in less time.
Answer:
63 m
Explanation:
Average speed of swimming = 45 m/min
Time = 1 minute 24 seconds
Converting time into minutes:
Formula:
Putting values, we get.
Thus, Alex swims for 63 m in 1 minute and 24 seconds.
