force of 10 lb is required to hold a spring stretched 4 in. beyond its natural length. How much work W is done in stretching it
1 answer:
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Answer:
The bulbs should be connected in parallel.
Explanation:
We want to find out a way to hook up 2 light bulbs and a battery so that when one bulb burns out or is disconnected the other bulbs stays lit.
We must connect the two bulbs in parallel so that even when one bulb is burns out, it will have no effect on the other bulb and the 2nd bulb will keep on working. The current flowing in each bulb will depend upon the resistance of each bulb and the voltage will be same across each bulb.
On the other hand, if we use a series circuit then if one bulb burns out then the there is no flow of current in the circuit and therefore, the second bulb will not be operational.
The current flowing through each bulb is given by
I = V/R
The voltage across each bulb is given by
V = IReq
Where I is the current and Req is the equivalent resistance of the two bulbs connected in parallel and is given by
Req = (R₁*R₂)/(R₁+R₂)
The connection diagram is attached where two bulbs are connected in parallel and are power with a battery.
Answer:
a) Since the height of the baseball at 99 m was 8.93 m and the fence at that distance is 3m tall, the hit was a home run.
b) The total distance traveled by the baseball was 108.7 m.
Explanation:
a) To know if the hit was a home run we need to calculate the height of the ball at 99 m:
Where:
: is the final height =?
: is the initial height = 1 m
: is the initial vertical velocity = v₀sin(45)
v₀: is the initial velocity = 32.5 m/s
g: is the gravity = 9.81 m/s²
t: is the time
First, we need to find the time by using the following equation:
Now, the height is:
Since the height of the baseball at 99 m was 8.93 m and the fence at that distance is 3m tall, the hit was a home run.
b) To find the distance traveled by the baseball first we need to find the time of flight:
By solving the above quadratic equation we have:
t = 4.73 s
Finally, with that time we can find the distance traveled by the baseball:
Hence, the total distance traveled by the baseball was 108.7 m.
I hope it helps you!
Answer:
a) W = 46.8 J and b) v = 3.84 m/s
Explanation:
The energy work theorem states that the work done on the system is equal to the variation of the kinetic energy
W = ΔK = -K₀
a) work is the scalar product of force by distance
W = F . d
Bold indicates vectors. In this case the dog applies a force in the direction of the displacement, so the angle between the force and the displacement is zero, therefore, the scalar product is reduced to the ordinary product.
W = F d cos θ
W = 39.0 1.20 cos 0
W = 46.8 J
b) zero initial kinetic language because the package is stopped
W - =
-K₀
W - fr d= ½ m v² - 0
W - μ N d = ½ m v
on the horizontal surface using Newton's second law
N-W = 0
N = W = mg
W - μ mg d = ½ m v
v² = (W -μ mg d) 2/m
v = √(W -μ mg d) 2/m
v = √[(46.8 - 0.30 4.30 9.8 1.20) 2/4.3 ]
v = √(31.63 2/4.3)
v = 3.84 m/s