Answer:
a) v=23.9 m/s
b) R=2646 N
Explanation:
According to Newton's second law the net force at the top is given by
∑F=-m*ac
according to
[tex]a_{c}=\frac{v^2}{r}[/tex]
∑F=[tex]-m*\frac{v^2}{r}[/tex]
a).
To lose contact this means that R=0 so the final equation is
[tex]R-m*g=-m*\frac{v^2}{r}[/tex]
[tex]-m*g=-m*\frac{v^2}{r}[/tex]
Solve to v
[tex]v^2=g*r[/tex]
[tex]v=\sqrt{g*r}=\sqrt{9.8*14.6}[/tex]
[tex]v=11.96\frac{m}{s}[/tex]
b).
v is the twice of part a so
[tex]v=2*11.96[/tex]
[tex]v=23.9\frac{m}{s}[/tex]
[tex]R_{m}-m_{m}*g-m_{p}=m*\frac{v^2}{r}[/tex]
Solve to Rm
[tex]R_{m}=m*\frac{v^2}{r}+(m_{m}+m_{p})*g[/tex]
[tex]R_{m}=m*\frac{23.9^2}{14.6}+(40+70)*9.8[/tex]
[tex]R_{m}=2646 N[/tex]
