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:
the electric field strength on the second one is 2.67 N/C.
Explanation:
the electric fiel on the first one is:
E1 = k×q/(r^2)
r^2 = k×q/(E1)
= (9×10^9)×(q)/(24.0)
= 375000000q
then the electric field on the second one is:
E2 = k×q/(R^2)
we know that R = 3r
R^2 = 9×r^2
E2 = k×q/(9×r^2)
= k×q/(9×375000000q)
= k/(9×375000000)
= (9×10^9)/(9×375000000)
= 2.67 N/C
Therefore, the electric field strength on the second one is 2.67 N/C.
This question involves the concepts of Newton's Second Law of Motion.
The acceleration of the bowling ball will be "0.67 m/s²".
<h3>Newton's Second Law of Motion</h3>
According to Newton's Second Law of Motion, when an unbalanced force is applied on an object, it produces an acceleration in it, in the direction of the applied force. This acceleration is directly proportional to the force applied and inversely proportional to the mass of the object. Mathematically,

where,
- a = acceleration = ?
- F = Magnitude of the applied force = 6 N
- m = Mass of the ball = 9 kg
Therefore,

a = 0.67 m/s²
Learn more about Newton's Second Law of Motion here:
brainly.com/question/13447525
#SPJ1
The increase in entropy is directly related to the increase in temperature.
The answer of <span> the change in electric potential difference is</span> -1.0 × 10^7 V. It is defined as the work done per unit charge. A potential difference of 1 V means that 1 joule of work is done per coulomb of charge or 1 V = 1 J C-1.