Answer:
0.025 m
Explanation:
From the question,
Applying Hook's law
F = ke................... Equation 1
Where F = Force, k = spring constant of the scale, e = maximum distance at which the spring will compress.
make e the subject of the equation
e = F/k....................... Equation 2
Given: F = 10 N, e = 395 N/m
Substitute these values into equation 2
e = 10/395
e = 0.025 m
100N to the left. Newton's 3rd law action and reaction
Answer:
They collide, couple together, and roll away in the direction that <u>the 2m/s car was rolling in.</u>
Explanation:
We should start off with stating that the conservation of momentum is used here.
Momentum = mass * speed
Since, mass of both freight cars is the same, the speed determines which has more momentum.
Thus, the momentum of the 2 m/s freight car is twice that of the 1 m/s freight car.
The final speed is calculated as below:
mass * (velocity of first freight car) + mass * (velocity of second freight car) = (mass of both freight cars) * final velocity
(m * V1) + (m * V2) = (2m * V)
Let's substitute the velocities 1m/s for the first car, and - 2m/s for the second. (since the second is opposite in direction)
We get:

solving this we get:
V = - 0.5 m/s
Thus we can see that both cars will roll away in the direction that the 2 m/s car was going in. (because of the negative sign in the answer)
For this, you need the v-squared equation, which is v(final)² = v(initial)² + 2aΔx
The averate acceleration is thus a = (v(final)² - v(initial)²) / 2Δx = (20² - 15²) / 2(50) = 175 / 100 = 1.75 m/s²
So the average acceleration is 1.75 m/s²
Answer:
The near point of an eye with power of +2 dopters, u' = - 50 cm
Given:
Power of a contact lens, P = +2.0 diopters
Solution:
To calculate the near point, we need to find the focal length of the lens which is given by:
Power, P = 
where
f = focal length
Thus
f = 
f =
= + 0.5 m
The near point of the eye is the point distant such that the image formed at this point can be seen clearly by the eye.
Now, by using lens maker formula:

where
u = object distance = 25 cm = 0.25 m = near point of a normal eye
u' = image distance
Now,



Solving the above eqn, we get:
u' = - 0.5 m = - 50 cm