Answer:
Explanation:
Given that
The window height is 2m
And the window is 7.5m from the ground
Then the total height of the window from the ground is 7.5+2=9.5m
It takes the ball 0.32sec travelled pass the window.
When the ball get to the window, it has an initial velocity (u') and when it gets to the top of the window it has a final velocity ( v')
Now using the equation of free fall during this window travels
S=ut-½gt² against motion.
S=2, g=9.81, t=0.32sec
Then,
S=u't-½gt²
2=u'×0.32-½×9.81×0.32²
2=0.32u'-0.5023
2+0.5032=0.32u'
Then, 0.32u'=2.5032
u'=2.5032/0.32
u'=7.82m/s
This is the initial velocity as the ball got the the window
Now, let analyse from the window bottom to the ground which is a distance of 7.5m
Using the equation of free fall again
v²=u²-2gH
In this case the final velocity (v) is the velocity when the ball reach the bottom of the window i.e u'=7.82m/s,
While u is the original initial velocity from the throw of the ball
Then,
u'²=u²-2gH
7.82²=u²-2×9.81×7.5
61.146=u²-147.15
61.146+147.15=u²
Then, u²=208.296
So, u=√208.296
u=14.43m/s
The initial velocity of the ball form the throw is 14.43m/s
Answer:
You can make a horizontale transverse by moving a slinky vertically up and down!
Explanation:
tar is very thick and viscous making it difficult to pour when cold which is why it's heated to extremely high temperatures when blacktop is being poured
Answer:
The answer is (d) is totally reflected
Explanation:
Using the total internal reflection concept.
This concept state that:
"If the angle of incidence is greater than the critical angle then the light will not refract but it will reflect back totally"
Using the above statement, as incident angle is 42 degree and critical angle is 41 degree it means incident angle is greater than the critical angle. Therefore, light will not refract but it will totally reflected.
The second option
You can see it in the name that see represents carbon and H represents hydrogen on the periodic table. The numbers after it are the amount of items that are in the molecule