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BTEC HNC maths

Vs=5sin(2pift-pi/3)
t=time
f=1MHz
Vs=volts

Find t when Vs is 3v

I’m getting t is 0.81s can someone say if that’s right. Head has been mashed with it.
Original post by david71
Vs=5sin(2pift-pi/3)
t=time
f=1MHz
Vs=volts

Find t when Vs is 3v

I’m getting t is 0.81s can someone say if that’s right. Head has been mashed with it.

That doesn't look right to me. Please post your working so that either I or one of the other helpers on this forum can have a look and see where you went wrong.
(edited 1 year ago)
Reply 2
Original post by old_engineer
That doesn't look right to me. Please post my working so that either I or one of the other helpers on this forum can have a look and see where you went wrong.


Thank you

Vs/5=sin(2pift-pi/3

sin-1Vs/5=sin-1(sin(2pift-pi/))

sin-1(Vs/5)=2pift-pi/3

sin-1Vs/5+pi/3=2pift

t = sin-1(Vs/5)+pi/3
—————-
2pif


t = sin-1 (3/5)+pi/3
————-
2pi1

t = 0.81
Original post by david71
Thank you

Vs/5=sin(2pift-pi/3

sin-1Vs/5=sin-1(sin(2pift-pi/))

sin-1(Vs/5)=2pift-pi/3

sin-1Vs/5+pi/3=2pift

t = sin-1(Vs/5)+pi/3
—————-
2pif


t = sin-1 (3/5)+pi/3
————-
2pi1

t = 0.81


Looks like f = 1 MHz, not 1 Hz.
Reply 4
Original post by mqb2766
Looks like f = 1 MHz, not 1 Hz.

If I enter 10^6 into that calculation, instead of 1, the calculator comes back with error! Where am I going wrong with it
Original post by david71
If I enter 10^6 into that calculation, instead of 1, the calculator comes back with error! Where am I going wrong with it


Not sure but there are plenty of online calculators.
Youd have to be specific about what youre actually typing in.
Original post by david71
If I enter 10^6 into that calculation, instead of 1, the calculator comes back with error! Where am I going wrong with it


Here are what you appear to be calculating and what I believe you should be calculating.
Reply 7
Original post by old_engineer
Here are what you appear to be calculating and what I believe you should be calculating.

Thank you

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