QCEVault

Vector calculus — Question 38

Original QCE Vault practice · 5 marks

Q38 · Practice questionComplex familiar5 marks

QUESTION 38 (5 marks)

A particle has position r(t)=5(cos⁡2t,sin⁡2t).\mathbf r(t)=5(\cos2t,\sin2t).
a)
Show that its speed is constant and determine that speed.
[2 marks]
b)
Show that a=−4r\mathbf a=-4\mathbf r.
[2 marks]
c)
Determine the period of the motion.
[1 mark]
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