A thread is wound 200 times round a reel of diameter 5cm. Use the value 3 for pie to find the approximate length of the thread in metres.

3 metres.

Step-by-step explanation:

The circumference of the reel is pi * d = 3 * 5  = 15 cm.

So the length of the thread = 200 * 15

= 3000 cm

= 30 metres.

L = 30 m

Step-by-step explanation:

lets make it simple and accurate

given

reel dia = 5 cm = 0.05 m

200 times round the reel

π = 3

reel O circumference = π d

Length of thread = Number of times round the reel x circumference

therefore,

L = 200 x (3 * 0.05)

L = 30 m

a. 12.5 kg

step-by-step explanation:

f = ma

so

m = f/a = (2500 n)/(200 m/s²) = 12.5 kg

1 n = 1 kg·m/s²

sorry i got nothing

step-by-step explanation: