Answer:
The ball takes 
to hit the ground.
Explanation:
• The second equation of motion represents the total distances travelled by an object in a time interval of 
with an initial speed of 
and acceleration 
.
• To find the time, ball takes to hit the ground, use the formula: 
Where, 
is time, is initial velocity, is acceleration and
is displacement.
• In this case, 
.
• Placing the value of the given initial velocity, 
and displacement,
in the above formula.
![& \Rightarrow 13 = 4 \cdot 9{t^2} \\& \Rightarrow {t^2} = \frac{{13}}{{4.9}} \\& \Rightarrow t = 1 \cdot 917sec \\\end{align}\]](https://tex.z-dn.net/?f=%26%20%20%5CRightarrow%2013%20%3D%204%20%5Ccdot%209%7Bt%5E2%7D%20%20%5C%5C%26%20%20%5CRightarrow%20%7Bt%5E2%7D%20%3D%20%5Cfrac%7B%7B13%7D%7D%7B%7B4.9%7D%7D%20%20%5C%5C%26%20%20%5CRightarrow%20t%20%3D%201%20%5Ccdot%20917sec%20%5C%5C%5Cend%7Balign%7D%5C%5D)
• Hence, ball takes to hit the ground.
Learn more about second equation of motion here:
brainly.com/question/19030143
Answer:
B
Explanation:
Friction always eventually stops whatever is in motion.
Answer:
Explanation:
The system ball-pin is modelled by the Principle of Moment Conservation:
The velocity of the bowling ball after the collision is:
When sphere A and B are brought in contact and separated, charge on each sphere becomes [2x10^-6 + (-4x10^-6)]/ 2 = -1x10^-6 C.
That is, charge is equally separated and is the average of charges on both spheres. The reason behind equal charge on both spheres after separation is, when they are kept in contact, their potential difference becomes same.
Answer:
Explanation:
Work done = ∫Fdx
= ∫(cx-3.00x²) dx
[ c x² / 2 - 3 x³ / 3 ]₀²
= change in kinetic energy
= 11-20
= - 9 J
[ c x² / 2 - x³ ]₀² = - 9
c x 2² / 2 - 2³ = -9
2c - 8 = -9
2c = -1
c = - 1/2
