Answer:
Explanation:
At the lowest point velocity is zero
loss of potential energy = gain of spring energy
= mgh = 1/2 k h² , h is vertical downward displacement , k is spring constant
2 mg = k h
h = 2mg / k
= (2 x .2 x 9.8) / 50
= .0784 m
P E ( gravitational) = - mgh
= - .2 x 9.8 x .0784
= - .1536 J
spring PE = + .1536 J
Total PE = 0
b )
At mid point ie at h = .0392 m
gravitational PE = .2 X 9.8 X .0392
= - .0768 J
Elastic PE = 1/2 X 50 X .0392² = .0384 J
Total = - .0768 J + .0384 J
= - .0384 J
At mid point total energy = 0
- .0384 + KE = 0
KE = .0384 J
c )
1/2 m v ² = .0384
v² = 2 x .0384 / .2
= .384
v = .6196 m / s
62 cm / s
Inertia is the property of an object that basically describes its resistance to change its state of motion.
For instance, if an object is still, inertia describes the "attitude" of the object to stay still (a force should be applied in order to move it). Similarly, if an object is moving by uniform motion (with constant speed), inertia refers to the "attitude" of the object to keep its uniform motion (again, a force should be applied to the object in order to change this state of motion).
The correct answer is C.
We will use Boyle's law that states that for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional.
P1 V1 = P2 V2
Where
P1 is initial pressure = 5 psi
V1 is initial volume = 20 cubic inch
P2 is final pressure = 10 psi
V2 is final volume = unknown
V2 = P1,V1 / P2
V2 = 20 × 5 / 10
V2 = 100/10
V2 = 10 cubic inches
Using the theorem of kinetic energy
1/2mVf² - 1/2mVi²= WF + Wp, Wp=0
WF = F. AB, AB=5m and F= 40N, m=20kg
so the final kinetic is KEf= 1/2mVf² = WF =<span>F. AB= 40*5=200J
</span>
the final velocity is 1/2mVf² <span>=200, implies Vf= sqrt(20)=2sqrt(5)m/s</span>
