Answer:
The comparison of unknown quantity with known quantity is called measurement.
When an object falls or is dropped from rest it's initial velocity is zero.
Using the equations for a motion in straight line. I can find the time it takes to reach 3.0 m down (half way).
x = vt - 4.9t²
-3 = 0 - 4.9t²
-3/-4.9 = t²
0.6122 = t²
0.7825 sec = t
v = v - gt
v = 0 - 9.8(0.7825)
v = -7.67 m/s
the negative denotes downward direction.
You could also solve the problem using potential and kinetic energy.
Since it starts with maximum PE and gets converted to KE when it hits the ground. mgh = mv²/2
mass cancels, use 3 meters for the halfway distance
-9.8(-3) = v²/2
29.4 * 2 = v²
√(58.8) = 7.67 m/s downwards
Point C would the greatest
Answer:
B 50kg
Explanation:
momentum =Mv
Then
momentum=M(v1+v2)=50(2*0.5)=50*1=50kg
Answer:
475 N/C
Explanation:
As we know that, the electric field in parallel plate capacitor is same (constant) throughout. And is potential gradient.
So, Electric field is given by
Electric field = potential gradient
Here, the potential change is 3.8V and the distance from negative plate to positive plate is 1.6 cm. The potential from negative plate to the center is (1.6/2)cm i.e., 0.8 cm.
But we have to take distance in SI units So, distance=
So, Electric field is
So, electric field is 475 Volts per meter.
Note : Also we can say 475 Newtons per coulomb