That is because work requires energy. According to the law of conservation of energy, it cannot be created or destroyed. When doing work, energy change forms and gets transferred to the object until it is released.
for example, when you lift up an object and place it on a higher elevation, you transferred energy to it and gave it potential energy. The potential energy is transformed into kinetic energy when the object falls down, and if it hits a surface, the energy will scatter, vibrating the areas around it and producing sound.
Also, work= force X distance. The energy does not go away, but rather get changed into some other form of energy
Eaither D or A bit I am leaning more towards D
Answer:
.
Explanation:
If the mass of an object is 
and the velocity of that object is 
, the linear momentum of that object would be 
.
Assume that the initial velocity of the mass is positive (
.) However, the direction of the velocity is reversed after the impact. Thus, the sign of the new velocity of the object would be negative- the opposite of that of the initial velocity. The new velocity would be 
.
Thus, the change in the velocity of the mass would be:
.
The change in the linear momentum of the mass would be:
.
Thus, the magnitude of the change of the linear momentum would be 
.
Answer:
F = 0.768 i ^ - 0.576 j ^ + 0.24 k ^
the correct answer is "b"
Explanation:
The magnetic force is
F = i l x B
The bold are vectors, in this case they give us the direction of the current and the magnetic field, for which we can solve as a determinant
![F = i \left[\begin{array}{ccc}x&y&z\\3&4&0\\0&5&12\end{array}\right]](https://tex.z-dn.net/?f=F%20%3D%20i%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%26y%26z%5C%5C3%264%260%5C%5C0%265%2612%5Cend%7Barray%7D%5Cright%5D)
resolver
F = i ^ (4 12 - 0) + j ^ (0- 3 12) + k ^ (3 5 - 0)
F = i (48 i ^ - 36 j ^ + 15 k⁾
in this case i is the value of the current flowing through the cable
i = 16 mA = 0.016 A
F = 0.768 i ^ - 0.576 j ^ + 0.24 k ^
When reviewing the different answers, the correct answer is "b"
Answer:
(a) a = - 201.8 m/s²
(b) s = 197.77 m
Explanation:
(a)
The acceleration can be found by using 1st equation of motion:
Vf = Vi + at
a = (Vf - Vi)/t
where,
a = acceleration = ?
Vf = Final Velocity = 0 m/s (Since it is finally brought to rest)
Vi = Initial Velocity = (632 mi/h)(1609.34 m/ 1 mi)(1 h/ 3600 s) = 282.53 m/s
t = time = 1.4 s
Therefore,
a = (0 m/s - 282.53 m/s)/1.4 s
<u>a = - 201.8 m/s²</u>
<u></u>
(b)
For the distance traveled, we can use 2nd equation of motion:
s = Vi t + (0.5)at²
where,
s = distance traveled = ?
Therefore,
s = (282.53 m/s)(1.4 s) + (0.5)(- 201.8 m/s²)(1.4 s)²
s = 395.54 m - 197.77 m
<u>s = 197.77 m</u>
