Answer:
Final Speed of Dwayne 'The Rock' Johnson = 15.812 m/s
Explanation:
Let's start out with finding the force acting downwards because of the mass of 'The Rock':
Dwayne 'The Rock' Johnson: 118kg x 9.81m/s = 1157.58 N
Now the problem also states that the kinetic friction of the desk in this problem is 370 N
Since the pulley is smooth, the weight of Dwayne Johnson being transferred fully, and pulls the desk with a force of 1157.58 N. The frictional force of the desk is resisting this motion by a force of 370 N. Subtracting both forces we get the resultant force on the desk to be: 1157.58 - 370 = 787.58 N
Now lets use F = ma to calculate for the acceleration of the desk:
787.58 = 63 x acceleration
acceleration = 12.501 m/s
Finally, we can use the motion equation:
here u = 0 m/s (since initial speed of the desk is 0)
a = 12.501 m/s
and s = 10 m
Solving this we get:
Since the desk and Mr. Dwayne Johnson are connected by a taught rope, they are travelling at the same speed. Thus, Dwayne also travels at 15.812 m/s when the desk reaches the window.
Answer:
True
Explanation:
Modern safer and cheaper nuclear reactors can not only meet the range of our long term energy demands, they can also fight global warming.
Modern techniques provide ways to reduce radioactive waste amount. "A closed fuel cycle may be switched on for new kinds of nuclear plants. Alternatively, the waste is chemically dissuaded to transform the reusable element into fuel. This implies that nuclear waste would not be buried.
<span>haha I used to think biology was so hard, i find it quite easy now.
Okay, so basically Osmosis is the movement of water molecules from a higher concentration to a lower concentration. Diffusion is generally the movement of a gradient from higher concentration to an area of lower concentration. Osmosis applies to water only, whereas diffusion, you have many types such as Passive transport [ movement of molecules from high- low, NO CELLULAR ENERGY needed! ] then you have faciliated diffusion ( basically uses a channel protein to allow big substances to go through the membrane : NO ENERGY needed]
OSMOSIS, the important thing to remember is that water ALWAYS flow towards the region with the higher concentration of the solute (ex: Salt is solute, water is solvent) solute is the thing that is being dissolved. Solvent is the one doing the dissolving. Hope this helped!</span>
Answer:
Mass of Jupiter = 4.173×10^15kg
Explanation:
Using Kepler's 3rd law, it states that the orbital period T is related to the distance,r as:
T^2 = GM/4 pi × r^3
Where G = universal gravitational constant
r = radius
M = masd of jupiter
Rearranging the formular to make M the subject of formular
T^2 × 4 pi = G M × r^3
(T^2 × 4 pi) / (G× r^3) = M
(1.24^2 × 4 × 3.142) /(6.672×10^-11)(4.11×10^8)^3
M = 19.32 /6.672×10^-11)(4.11×10^8)^3
M = 19.32 / 4.63 ×10^15
M = 4.173×10^15kg
Answer:
2100 J
Explanation:
Parameters given:
Force acting on the object, F = 420 N
Distance moved by object, d = 5m
The change in kinetic energy of an object is equal to the work done by a force acting on the object:
W = F * d
∆KE = F * d
∆KE = 420 * 5
∆KE = 2100 J
