The most accurate answer is C. B could be true, but it's not just breathing in
Answer:
1.59 seconds
12.3 meters
but if you are wise you will read the entire answer.
Explanation:
This is a good question -- if not a bit unusual. You should try and understand the details. It will come in handy.
Time
<u>Given</u>
a = 0 This is the critical point. There is no horizontal acceleration.
d = 20 m
v = 12.6 m/s
<u>Formula</u>
d = vi * t + 1/2at^2
<u>Solution</u>
Since the acceleration is 0, the formula reduces to
d = vi * t
20 = 12.6 * t
t = 20 / 12.6
t = 1.59 seconds.
It takes 1.59 seconds to hit the ground
Height of the building
<u>Givens</u>
t = 1.59 sec
vi = 0 Another critical point. The beginning speed vertically is 0
a = 9.8 m/s^2 The acceleration is vertical.
<u>Formula</u>
d = vi*t + 1/2 a t^2
<u>Solution</u>
d = 1/2 a*t^2
d = 1/2 * 9.8 * 1.59^2
d = 12.3 meters.
The two vi's are not to be confused. The horizontal vi is a number other other 0 (in this case 12.6 m/s horizontally)
The other vi is a vertical speed. It is 0.
(a) 
For an electromagnetic wave incident on a surface, the radiation pressure is given by (assuming all the radiation is absorbed)
where
I is the intensity
c is the speed of light
In this problem, 
; substituting this value, we find the radiation pressure:
the force exerted on the Earth depends on the surface considered. Assuming that the sunlight hits half of the Earth's surface (the half illuminated by the Sun), we have to consider the area of a hemisphere, which is
where
is the Earth's radius. Substituting,
And so the force exerted by the sunlight is
(b) 
The gravitational force exerted by the Sun on the Earth is
where
G is the gravitational constant
is the Sun's mass
is the Earth's mass
is the distance between the Sun and the Earth
Substituting,
And so, the radiation pressure force on Earth as a fraction of the sun's gravitational force on Earth is
Answer:
A conducting pattern is a pattern in which your dominant hand follows in order to establish beats and tempo to the choir. Conductors that are directing large orchestras and choirs will often times use a baton so that the entire group can clearly see the motions.
Explanation:
Answer:
Zero
Explanation:
According to Newton's second law, the net force acting on an object is equal to the product between the object's mass and its acceleration:
F = ma
For the hockey puck, there are no forces acting on it during its motion, since ice friction and air resistance are negligible. This means that the net force is zero:
F = 0
But this means that the acceleration is also zero:
a = 0
So the hockey puck is moving already at constant velocity. Therefore, there is no need for additional forces.
