two seconds after the projection upwards from level ground , a projectile is moving at 30 degree to the horizontal after one more second its velocity is horizontal.the velocity of the projection was in ? (g=10m/s)

Question

anonymous · Answer

20root3 is the answer plzz solve for it

aravindg · Answer

@shivam_bhalla  , @cshalvey

anonymous · Answer

@.Sam.

anonymous · Answer

Yes @AravindG .

aravindg · Answer

pls dont help him guys he is making us do his hwork

anonymous · Answer

no u tell me the steps i will do it

anonymous · Answer

@shameer, would you like to show your attempt to solve the problem?

aravindg · Answer

dont act like u r wrking..COZ  U R NOT!!

anonymous · Answer

i dont need the final answer because i know that it is 20root3

anonymous · Answer

yes i will show my work @shivam_bhalla

anonymous · Answer

Then Please show.  We are waiting.

anonymous · Answer

ok

anonymous · Answer

i think 1st  i have to find this   T=2usin theta/g  then find  u  is that correct  @shivam_bhalla

anonymous · Answer

@shameer1 , when does the projectile have only horizontal velocity ??

anonymous · Answer

when it is thrown horizontally/..

anonymous · Answer

$$\text{For the vertical velocity at }t_0\text{, we can use the equation for the time to reach maximum height.}$$$$t_h = 3 = \frac{v_0\sin(\theta)}{g}$$$$\implies v_0\sin(\theta) = 30 \text{m/s}$$
Now if we can figure out horizontal velocity... :(

anonymous · Answer

And then use pythagorean theorem to find the velocity of projection

anonymous · Answer

hey i got it as 15root3    but it should be 20root3

ajprincess · Answer

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