Workbook Physics

$7-11$ Circular Motion Dynamics Problems with Components

A simple pendulum consists of a $140$ g ball tied to a $2\mathrm{.}0$ m $-$long string. The tension in the string is $1\mathrm{.}5$ N as the ball passes through the position shown, where $$ is $18.$

a$)$ What is the velocity of the ball at this point?

b$)$ Will the tension increase or decrease as the ball approaches the bottom of its swing?

A curved section of road has a radius of $450$ m and is banked at a $3\mathrm{.}0$ angle. A typical $1500$ kg car traveling at design speed does not need friction to safely make the turn.

a$)$ What is the design speed for this section of roadway?

b$)$ If the mass of the car is doubled, does the design speed change?

As a child on a tire swing revolves in a horizontal circle, the $3\mathrm{.}6-m-$long rope maintains a $34$ angle from the vertical. The child and tire have a combined mass of $50\mathrm{.}0$ kg $.$

a$)$ What is the tension in the rope?

b$)$ What is the velocity of the child?

Answers: $1)1\mathrm{.}7\frac{m}{s},$ increase

$15\frac{m}{s},$ no

$590N,3\mathrm{.}6\frac{m}{s}$

$202$