The Gravitationa potential energy of the mass (PEG) is given by:
where
m is the mass
g is the gravitational acceleration
h is the heigth of the mass above the reference level (the ground)
In this problem,
and
, therefore the gravitational potential energy of the mass is:
(a) The stone travels a vertical distance <em>y</em> of
<em>y</em> = (12.0 m/s) <em>t</em> + 1/2 <em>g t</em> ²
where <em>g</em> = 9.80 m/s² is the acceleration due to gravity. Note that this equation assume the downward direction to be positive, and that <em>y</em> = 0 corresponds to the height from which the stone is thrown.
So if it reaches the ground in <em>t</em> = 1.54 s, then the height of the building <em>y</em> is
<em>y</em> = (12.0 m/s) (1.54 s) + 1/2 (9.80 m/s²) (1.54 s)² ≈ 30.1 m
(b) The stone's (downward) velocity <em>v</em> at time <em>t </em>is
<em>v</em> = 12.0 m/s + <em>g t</em>
so that after <em>t</em> = 1.54 s, its velocity is
<em>v</em> = 12.0 m/s + (9.80 m/s²) (1.54 s) ≈ 27.1 m/s
(and of course, speed is the magnitude of velocity)
plane is flying at an altitude of 70 m
now if an object is dropped from it then time taken by object to drop on ground will be given as
here initial speed in vertical direction must be zero as plane is moving horizontal
given that
y = 70 m
a = 9.8 m/s^2
now since the plane is moving horizontally with speed v = 44 m/s
so the horizontal distance moved by the object will be
so the distance moved by the box is 166.3 m
Answer:
The answer is the second option.
Explanation:
This is a higher temperature than Onnes's experiment, and it will allow for a broader use of superconductors.
Answer:
0.125 volts
Explanation:
The induced emf can be sufficient to stimulate neuronal activity.
One such device generates a magnetic field within the brain that rises from zero to 1.5 T in 120 ms.
We need to find the induced emf within a circle of tissue of radius 1.6 mm and that is perpendicular to the direction of the field. The formula for the induced emf is given by :
Where
is magnetic flux
So,
So, the induced emf is equal to 0.125 volts.
