A hypothesis is an educated guess, while a theory is usually a tested, well substained explanation of something.
Answer:
a) about 20.4 meters high
b) about 4.08 seconds
Explanation:
Part a)
To find the maximum height the ball reaches under the action of gravity (g = 9.8 m/s^2) use the equation that connects change in velocity over time with acceleration.
In our case, the initial velocity of the ball as it leaves the hands of the person is Vi = 20 m/s, while thw final velocity of the ball as it reaches its maximum height is zero (0) m/s. Therefore we can solve for the time it takes the ball to reach the top:
Now we use this time in the expression for the distance covered (final position Xf minus initial position Xi) under acceleration:
Part b) Now we use the expression for distance covered under acceleration to find the time it takes for the ball to leave the person's hand and come back to it (notice that Xf-Xi in this case will be zero - same final and initial position)
To solve for "t" in this quadratic equation, we can factor it out as shown:
Therefore there are two possible solutions when each of the two factors equals zero:
1) t= 0 (which is not representative of our case) , and
2) the expression in parenthesis is zero:
Answer:
a )1.851
b ) 32.68°
Explanation:
The relation between critical angle and index of refraction is as follows
Sin C = 1 / μ
C is critical angle and μ is refractive index.
Given C = 47.3
Sin 47.3 = 1 / μ
0.735 = 1 / μ
μ = 1 / .735
= 1.36
This is with respect to ethanol .
1.36 = refractive index of material / refractive index of ethanol
refractive index of material = 1.36 x refractive index of ethanol
= 1.36 x 1.361 = 1.851
If critical angle for this substance be A
Sin A = 1 / 1.851 = .54
A = 32.68° .
That's a weird graph, but judging from the units the acceleration is the slope of the graph.
a = (0.8 - 0.3)/(0.16 - 0.055) = 4.76 m/s²