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# M1 Vectors question help watch

1. I'm struggling with this vectors question for homework...

A particle P of mass 1.5 kg is moving under the action of a constant force. P has an acceleration of magnitude (62.25)^1/2 in direction (2i-5j) N. Initially P has velocity (2i+3j) m/s. Find
a) the acceleration of P, in terms of i and j
b) the velocity of P, in terms if i and j, when P has been moving for 4 seconds

Could you please help me.. I think it somehow uses the SUVAT equations but I'm not quite sure

2. (Original post by spurs_till_i_die)
I'm struggling with this vectors question for homework...

A particle P of mass 1.5 kg is moving under the action of a constant force. P has an acceleration of magnitude (62.25)^1/2 in direction (2i-5j) N. Initially P has velocity (2i+3j) m/s. Find
a) the acceleration of P, in terms of i and j
b) the velocity of P, in terms if i and j, when P has been moving for 4 seconds

Could you please help me.. I think it somehow uses the SUVAT equations but I'm not quite sure

I'm assuming (2i-5j) is the constant force when doing this. Acceleration should be in the same direction as the force so I used similar triangles to figure the i and j components (you are given the magnitude which would be your hypotenuse). Once you've figured that out the rest should be easy.
3. (Original post by k4l397)
I'm assuming (2i-5j) is the constant force when doing this. Acceleration should be in the same direction as the force so I used similar triangles to figure the i and j components (you are given the magnitude which would be your hypotenuse). Once you've figured that out the rest should be easy.
If the force is 8in direction 2i-5j then the acceleration must be in the same direction, so it is (2i-5j)x for some value of x and the magnitude would then be sqrt((2x)^2+(5x)^2) which we know is sqrt(62.25) so x^2=62.5/9

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