Imagine a ball is moving on the following horizontal line.
. . . . . . . . . . . . . . . . . . . O. . . . . . . . . . . . . . . . . .
Take right as positive. O is the starting point of the ball. Denote the ball by o.
. . . . . . . . . . . . . . . . . . . O. . . . . . . ... . . o . . . . . .
Assume the ball is moving to the right. It has positive displacement since it is on the right of O, and positive velocity since its positive displacement is increasing.
.ñ
. . . . . . . . . . . . . . . . . . . O. . . . o . . . . . . . . . . . . .
Now the ball is returning to O. It still has positive displacement since its current position is still on the right of O. However, its velocity is negative since its positive displacement is decreasing and the direction of the velocity vector points left, which is the negative side.
By now you should be able to come up with a scenario where the ball has negative displacement and positive velocity.
You can observe the same phenomenon in daily life. Say, as a stretched spring bounces to its starting position, if we let the returning direction be positive, the string has negative displacement since it is on the negative direction, but has positive velocity. Bungee jump can also used to illustrate the phenomenon.
From the question, The kinetic energy of the fired arrow is equal to the work done by the bale of hale in stopping the arrow.
We make use of the following formula
mv²/2 = F'd................... Equation 1
Where
- m = mass of the arrow
- v = velocity of the arrow
- F' = average stopping force acting on the arrow
- d = distance of penetration
Make F' the subject of the equation
F' = mv²/2d.................. Equation 2
From the question,
Given:
- m = 20 g = 0.02 kg
- v = 60 m/s
- d = 40 cm = 0.4 m
Substitute these values into equation 2
Hence, The average stopping force acting on the arrow is 90 N
Learn more about average stooping force here: brainly.com/question/13370981
Answer:
Explanation:
m = Mass of proton = 
v = Speed of proton = 0.5c = 
Circumference of the colider is 7 km
Centripetal acceleration is 
Force on protons is 
Answer:
Option B. 3.0×10¯¹¹ F.
Explanation:
The following data were obtained from the question:
Potential difference (V) = 100 V.
Charge (Q) = 3.0×10¯⁹ C.
Capacitance (C) =..?
The capacitance, C of a capacitor is simply defined as the ratio of charge, Q on either plates to the potential difference, V between them. Mathematically, it is expressed as:
Capacitance (C) = Charge (Q) / Potential difference (V)
C = Q/V
With the above formula, we can obtain the capacitance of the parallel plate capacitor as follow:
Potential difference (V) = 100 V.
Charge (Q) = 3.0×10¯⁹ C.
Capacitance (C) =..?
C = Q/V
C = 3.0×10¯⁹ / 100
C = 3.0×10¯¹¹ F.
Therefore, the capacitance of the parallel plate capacitor is 3.0×10¯¹¹ F.
Answer:
0.5mv^2=50, v=5, 25/2×m=50, m=50×2/25, So, the answer is 4
