78.4 joules is the energy of a 4 kg apple that is sitting on a 2 m high tree branch.
<u>Explanation:
</u>
When an apple falls to the ground from a tree, its positional energy (stored as potential gravitational energy) turns into kinetic energy, during a fall. Chemical potential energy is chemical energy because it is food and potential energy as it can still have ability to move. So, in the given case, kinetic energy is zero.
To find potential energy, the formula would be
Where, given
m – Mass – 4 kg
(Known value)
h – Height - 2 m
Substitute these values, we get
a) Southward you need to apply right hand rule. If you close your hand to the east, your thumb will indicate south.
b) Given the equation for Magnetic Force
Replacing
c) Given the second Newton's Law by
Given the electric force by,
Within that unit of blood, you are going to have plasma, white blood cells, red blood cells, and platelets.
Radium........ Hope this helps :)
Answer:
<em>Option b is correct: 4.1 s</em>
Explanation:
<u>Vertical Launch</u>
An object launched thrown vertically upward where air resistance is negligible, reaches its maximum height in a time t, given by the equation:
![\displaystyle t=\frac{v_o}{g}\qquad\qquad[1]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20t%3D%5Cfrac%7Bv_o%7D%7Bg%7D%5Cqquad%5Cqquad%5B1%5D)
Where vo is the initial speed and g is the acceleration of gravity g=9.8 
.
Once the object reaches that point, it starts a free-fall motion, whose speed is (downward) given by:
![v_f=g.t\qquad\qquad[2]](https://tex.z-dn.net/?f=v_f%3Dg.t%5Cqquad%5Cqquad%5B2%5D)
The object considered in the question is thrown with vo=25 m/s. The time taken to reach the maximum height is given by [1]:
The object starts its falling motion and at some time, it has a speed of vf=15 m/s. Let's find the time by solving [2] for t:
The total time taken by the object to go up and down is
a. This option is incorrect because it's far away from the answer.
d. This option is incorrect because it's far away from the answer.
b. This option is correct because it's a good approximation to the calculated answer.
e. This option is incorrect because it's far away from the answer.
c. This option is incorrect because it's far away from the answer.
