Answer:
Explanation:
Given that
g=9.8m/s²
The spring constant is
k=50N/m
The length of the bungee cord is
Lo=32m
Height of bridge which one end of the bungee is tied is 91m
A steel ball of mass 92kg is attached to the other end of the bungee.
The potential energy(Us) of the steel ball before dropped from the bridge is given as
P.E= mgh
P.E= 92×9.8×91
P.E= 82045.6 J
Us= 82045.6 J
Potential energy)(Uc) of the cord is given as
Uc= ½ke²
Where 'e' is the extension
Then the extension is final height extended by cord minus height of cord
e=hf - hi
e=hf - 32
Uc= ½×50×(hf-32)²
Uc=25(hf-32)²
Using conservation of energy,
Then,
The potential energy of free fall equals the potential energy in string
Uc=Us
25(hf-32)²=82045.6
(hf-32)² = 82045.6/25
(hf-32)²=3281.825
Take square root of both sides
√(hf-32)²=√(3281.825)
hf-32=57.29
hf=57.29+32
hf=89.29m
We neglect the negative sign of the root because the string cannot compressed
Gases have heavier molecules. Since all gases have the same average kinetic energy at the same temperature, lighter molecules move faster and heavier molecules move slower on average.
Assume the motion when you are in the car or in the school bus to go to the school.
To describe the motion the first thing you need is a point of reference. Assume this is your house.
This should be a description:
- When you are sitting and the car has not started to move you are at rest.
- The car starts moving from rest, gaining speed, accelerating. You start to move away from your house, with a positive velocity (from you house to your school) and positive acceleration (velocity increases).
- The car reaches a limit speed of 40mph, and then moves at constant speed. The motion is uniform, the velocity is constant, positive, since you move in the same direction), and the acceleration is zero.
- When the car approaches the school, the driver starts to slow down. Then, you speed is lower but yet the velocity is positive, as you are going in the same direction. The acceleration is negative because it is in the opposite direction of the motion.
- When the car stops, you are again at rest: zero velocity and zero acceleration.
- In all the path your velocity was positive, constant at times (zero acceleration) and variable at others (accelerating or decelerating).
- When you comeback home, then you can start to compute negative velocities, as you will be decreasing the distance from your point of reference (your house).
Answer:
Because of the formula
Explanation:
In this problem we are describing two different processes:
- Nuclear fission occurs when a heavy, unstable nucleus breaks apart into two or more lighter nuclei
- Nuclear fusion occurs when two (or more) light nuclei fuse together producing a heavier nucleus
In both cases, the total mass of the final products is smaller than the total mass of the initial nuclei.
According to Einsten's formula, this mass difference has been converted into energy, as follows:
where:
E is the energy released in the reaction
is the mass defect, the difference between the final total mass and the initial total mass
is the speed of light
From the formula, we see that the factor is a very large number, therefore even if the mass defect is very small, nuclear fusion and nuclear fission release huge amounts of energy.
Answer:
B, E, F
Explanation:
Because cyberbullying happens online, text messages, social media networks, and chat rooms can all have cyberbullying, because they are all ways to chat online. D does not apply, because on most websites there are not ways to chat.