Answer:
Speed of lighter ball is 4 m/s.
Explanation:
Applying the principle of conservation of linear momentum,
momentum before collision = momentum after collision.

+
= 
- 

= 3 kg,
= 8 m/s,
= 2 kg,
= 0 m/s ( since it is at rest),
= 2 m/s,
= ?
(3 x 8) + (2 x 0) = (8 x 2) - (2 x
)
24 + 0 = 16 - 2
2
= 16 - 24
2
= -8
= 
= -4 m/s
This implies that the light ball moves at the speed of 4 m/s in the opposite direction of the heavier ball after collision.
Answer:
I would need more electrons 1.3125 10¹⁰ electrons
Explanation:
Static electricity is formed by induced charges in each part of the system, so the net charge does not change.
Let us analyze the situation presented, if the carpet acquires a positive charge, so that it does not alter the total charge in man, it should acquire a negative charge, to have a net negative charge I would need more electrons that have a negative charge.
We can know the number of electrons by a rule of proportions, if an electron has a charge of 1.6 10-19 C for a charge of 2.15 10-9 C how many electrons are needed
# = 2.15 10⁻⁹ /1.6 10⁻¹⁹
# = 1.3125 10¹⁰ electrons
The number is very high for which we will not worry about rounding since the number of electrons must be an integer
The ball's horizontal and vertical velocities at time
are


but the ball is thrown horizontally, so
. Its horizontal and vertical positions at time
are


The ball travels 22 m horizontally from where it was thrown, so

from which we find the time it takes for the ball to land on the ground is

When it lands,
and


Answer:
1) 
2) 
3) 

Explanation:
Given:
width of river, 
speed of stream with respect to the ground, 
speed of the swimmer with respect to water, 
<u>Now the resultant of the two velocities perpendicular to each other:</u>



<u>Now the angle of the resultant velocity form the vertical:</u>



- Now the distance swam by the swimmer in this direction be d.
so,



Now the distance swept downward:



2)
On swimming 37° upstream:
<u>The velocity component of stream cancelled by the swimmer:</u>



<u>Now the net effective speed of stream sweeping the swimmer:</u>



<u>The component of swimmer's velocity heading directly towards the opposite bank:</u>



<u>Now the angle of the resultant velocity of the swimmer from the normal to the stream</u>:



- Now let the distance swam in this direction be d'.



<u>Now the distance swept downstream:</u>



3)
Time taken in crossing the rive in case 1:



Time taken in crossing the rive in case 2:



ANSWER
8.99 F
EXPLANATION
We know that two capacitors of capacitances 2.8 F and 5.57 F are connected in series, while a third capacitor of capacitance 7.13 F is connected in parallel to that combination,
The capacitance works similarly to the resistance, except that when capacitors are connected in parallel, their capacitances add up, while when they are connected in series, the equivalent capacitance is like we were finding the equivalent resistance of resistors connected in parallel,

Hence, the total capacitance is 8.99 F, rounded to the nearest hundredth.