For the answer to the question above, <span>at the end, the KE = 1/2mv^2 = (1/2)(2000)(2^2) = 4000 J This must equal the net work acting on the car. W=Fd The net force is 1140-950= 190N. so, d=W/F = 4000/190 = 21.05 m
I hope my answer helped you.</span>
Answer:
They are too busy doing their own work
1. Resistor
2. Insulator
3. Current
4. Semiconductor
5. Conductor
Answer:
Explanation:
The missing question her is: What is the change in momentum of the baseball?
According to the Impulse-Momentum Theorem, we have:
Where:
is the exerted force
is the time interval
is the change in momentum
So, in the case of the bat and the ball we have:
For the bat:
(1)
For the ball:
(2)
Since is the same for both the bat and the ball, their impulses are equal in magnitude but in opposite direction according to Newton's 3rd law of motion. Hence:
(3)
Then:
(4)
Where:
Being , ,
Being
Then (4) is rewritten as:
(5)
Since :
(6)
Isolating :
(7)
(8)
(9)
Now, the change in momentum of the baseball is:
(10)
Substituting (9) in (10):
(11)
Finally:
This is the change in momentum of the baseball. Note it is negative because its initial velocity is greater than its final velocity
Hi there!
a.
Use the formula d = st to solve:
d = 20 × 0.5 = 10m
150 - 10 = 140m away when brakes are applied
b.
Use the following kinematic equation to solve:
vf² = vi² + 2ad
Plug in known values:
0 = 20² + 2(150)(a)
Solve:
0 = 400 + 300a
-300a = 400
a = -4/3 (≈ -1.33) m/s² required
c.
Use the following kinematic equation to solve:
vf = vi + at
0 = 20 - 4/3t
Solve:
4/3t = 20
Multiply both sides by 3/4 for ease of solving:
t = 15 sec