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Mechanics 2 (OCR) Chapter 1 Questions help!

Would someone please be able to explain how to work out the following questions? I can work out the displacements but am having real difficulty working out the velocities, specifically the vertical velocity.

A particle is projected with speed 35ms^(-1) at an angle of 40 degrees above the horizontal. Calculate the horizontal and vertical components of the displacement of the particle after 3 seconds. Calculate also the horizontal and vertical components of the velocity of the particle at this instant.

A particle is projected with speed 9ms^(-1) at 40 degrees to the horizontal. Calculate the time the particle takes to reach its maximum height, and find its speed at that instant.

These are questions 5 & 7 of Exercise 1B from the OCR Mechanics 2 book.

Thanks

Reply 1

Lapis lazuli

This is the way i did these sorts of questions.

Resolve the intial speed in horizontal and vertical components. eg 35cos40, 35sin40

so for the

horiontal motion ------> u=35cos40=v so s=tu

vertical motion -------> u=35sin40 a =-9.8 t=3

and you can go from there?