Answer:
M= -0.51
Explanation:
After i calculated my v to be -5.2cm from the formula 1/f=1/v+1/u
Then m=v/u which is -0.51
Answer:
I may not have the answer so i'll just give up some hints.
Multiply the time by the acceleration due to gravity to find the velocity when the object hits the ground. If it takes 9.9 seconds for the object to hit the ground, its velocity is (1.01 s)*(9.8 m/s^2), or 9.9 m/s. Choose how long the object is falling. In this example, we will use the time of 8 seconds. Calculate the final free fall speed (just before hitting the ground) with the formula v = v₀ + gt = 0 + 9.80665 * 8 = 78.45 m/s . Find the free fall distance using the equation s = (1/2)gt² = 0.5 * 9.80665 * 8² = 313.8 m .h = 0.5 * 9.8 * (1.5)^2 = 11m. b. V = gt = 9.8 * 1.5 = 14.7m/s. A feather and brick dropped together. Air resistance causes the feather to fall more slowly. If a feather and a brick were dropped together in a vacuum—that is, an area from which all air has been removed—they would fall at the same rate, and hit the ground at the same time.When an object's point is taller the thing that is going down it will go faster than when the point is lower. EXAMPLE: The object is the tennis ball if you drop it down the higher hill it will be faster than if you drop it down a shorter hill. In other words, if two objects are the same size but one is heavier, the heavier one has greater density than the lighter object. Therefore, when both objects are dropped from the same height and at the same time, the heavier object should hit the ground before the lighter one.
I hope my little bit (big you may say) hint help you with your question.
The answer is 9.8, did this last year in AP Science
1. A. The SI unit for current is the ampere.
2. C. The unit for resistance = ohm.
3. B. EMF is measured in volts.
4. B. Electric current is the flow of charged particles, i.e. electrons.
5. B or C. All other answers are metals.
6. C. The dimensions of a material don't affect its resistance.
7. D. Ohm's law: current = voltage / resistance, 12/4 = 3.
8. B. Batteries transform chemical energy into electrical energy.
9. A. Metals are generally good conductors.
Answer:
T = 1.12 10⁻⁷ s
Explanation:
This exercise must be solved in parts. Let's start looking for the electric field in the axis of the ring.
All the charge dq is at a distance r
dE = k dq / r²
Due to the symmetry of the ring, the field perpendicular to the axis is canceled, leaving only the field in the direction of the axis, if we use trigonometry
cos θ =
dEₓ = dE cos θ
cos θ = x / r
substituting
dEₓ =
DEₓ = k dq x / r³
let's use the Pythagorean theorem to find the distance r
r² = x² + a²
where a is the radius of the ring
we substitute
dEₓ =
we integrate
∫ dEₓ =k \frac{x}{(x^2 + a^2 ) ^{3/2} } ∫ dq
Eₓ = 
In the exercise indicate that the electron is very central to the center of the ring
x << a
Eₓ =
if we expand in a series
we keep the first term if x<<a
Eₓ =
the force is
F = q E
F = 
this is a restoring force proportional to the displacement so the movement is simple harmonic,
F = m a
the solution is of type
x = A cos (wt + Ф)
with angular velocity
w² =
angular velocity and period are related
w = 2π/ T
we substitute
4π² / T² = \frac{keQ}{m a^3}
T = 2π
let's calculate
T = 2π
T = 2π pi 
T = 2π 17.9 10⁻⁹ s
T = 1.12 10⁻⁷ s