A Professor Holds an Eraser Against a Vertical Chalkboard by Pushing

question 42

Multiple Choice

A professor holds an eraser against a vertical chalkboard by pushing horizontally on it. He pushes with a force that is much greater than is required to hold the eraser. The force of friction exerted by the board on the eraser increases if he:

• A) pushes with slightly greater force
• B) pushes with slightly less force
• C) stops pushing
• D) pushes so his force is slightly downward but has the same magnitude
• E) pushes so his force is slightly upward but has the same magnitude

---

Definitions:

Initial Margin

The portion of the purchase price that an investor must deposit when buying securities on margin, serving as a form of collateral.

Initial Investment

The amount of money used to start a business venture, acquire an asset, or invest in a financial product.

Short 100 Shares

The selling of 100 shares that are not currently owned, with the expectation of buying them back at a lower price for a profit.

Initial Margin

The minimum amount of capital required to open a new position in the market, designed as a security for the broker against potential losses.