A student measured 15s for the 20 complete oscillations for an object of 200g attached at the free end of a spring. Calculate the period of oscillation (T) and the spring constant (k).

My work (just wanted to ask for opinions if this is right):
T = 2π√(m/k)

T = 20 oscillation/15 seconds = 1.33 s for 1 oscillation

1.33 = 2π√(0.2 kg/k)
k = 0.0456 N/kg

T = 1.33, k = 0.0456 N/kg

Thanks in advance for any replies.

where did you get period as 1.33 seconds?

15sec/20=.75 sec= period

it is 1.33 oscillation per second...= frequency...

Your calculations and approach are almost correct, but there is a slight mistake in your final calculation of the spring constant.

Here's how you can calculate the period of oscillation (T) and the spring constant (k):

To find T, divide the total time by the number of oscillations:
T = (total time) / (number of oscillations)

In this case, the total time for 20 oscillations is given as 15 seconds:
T = 15 s / 20 = 0.75 s

So the period of oscillation is T = 0.75 s.

To find the spring constant (k), you can use the formula you mentioned:

T = 2π√(m/k)

Rearranging the formula to solve for k:

k = (4π²m) / T²

Where:
m = mass of the object = 0.2 kg
T = period of oscillation = 0.75 s

Now, plug in the values and calculate:

k = (4π² * 0.2 kg) / (0.75 s)²

k ≈ 1.68 N/m (rounded to two decimal places)

So the spring constant is k ≈ 1.68 N/m.

Therefore, the correct values are:
T = 0.75 s
k ≈ 1.68 N/m