<span>if we assume the origin is at the dropping point and the object is merely dropped and not thrown up or down then y0 = 0 and v0 = 0. The equation reduces to </span>
<span>y = 0 + 0t + ½gt² </span>
<span>y = ½gt² </span>
<span>t = √(2y/g) </span>
<span>in the ft - lb - s system </span>
<span>y = -100 ft </span>
<span>g = -32.2 ft / s² </span>
<span>t = √(2y/g) </span>
<span>t = √(2(-100) / (-32.2)) </span>
<span>t = 2.5 s</span>
We have that the momentum p is given by the formula p=mv where m is the mass and v is the velocity. Since for A p=-14kgm/s and m=7, we have that the velocity is -14/7=-2m/s. Hence its speed is 2 m/s.
For b we have that p=15kgm/s and v=3m/s. Because m=p/v, we have m=3kg.
We also have that the momentum is conserved in this system. Hence, the net sum of the momentum of the 2 snowballs equals the momentum of the single giant ball. Hence, p(total)=p(combined)=-14+15=1kgm/s (momentum is a vector; the positive sign means that it tends to the positive direction).
Answer:
<em>a) 0.72 V</em>
<em>b) 19.2 mA</em>
<em>c) 2.304 Watts</em>
Explanation:
A transformer is used to step-up or step-down voltage and current. It uses the principle of electromagnetic induction. When the primary coil is greater than the secondary coil, the it is a step-down transformer, and when the primary coil is less than the secondary coil, the it is a step-up transformer.
number of primary turns =
= 500 turns
input voltage =
= 120 V
number of secondary turns =
= 3 turns
output voltage =
= ?
using the equation for a transformer

substituting values, we have


= 360/500 =<em> 0.72 V</em>
<em></em>
b) by law of energy conservation,

where
= input current = ?
= output voltage = 3.2 A
= output voltage = 0.72 V
= input voltage = 120 V
substituting values, we have
120
= 3.2 x 0.72
120
= 2.304
= 2.304/120 = 0.0192 A
= <em>19.2 mA</em>
<em></em>
c) power input = 
==> 0.0192 x 120 = <em>2.304 Watts</em>
Answer:
Explanation:
In a L C R circuit, the average power is given by

As given in the question
CosФ = R / Z
And we know that

So


Answer:
6
Explanation:
The median is found by listing the numbers in order numerically and finding the one that is right in the middle. In this case you have 1, 3, 5, 6, 7, 12, 15 where the middle term is 6.