A Uniform Ladder Is 10 Cm Long and Weighs 400 $\degree$

question 24

Multiple Choice

A uniform ladder is 10 cm long and weighs 400 N. It rests with its upper end against a frictionless vertical wall. Its lower end rests on the ground and is prevented from slipping by a peg driven into the ground. The ladder makes a 30 $\degree$ angle with the horizontal. The force exerted on the wall by the ladder is:

• A) 48 N
• B) 74 N
• C) 120 N
• D) 350 N
• E) 610 N

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Definitions:

Premack's Probability-Differential Theory

A theory that suggests more probable behaviors will reinforce less probable behaviors.

Response Deprivation Theory

A theory suggesting that behavior can serve as a reinforcement when access to the behavior is restricted and its frequency falls below a preferred level.

Negative Reinforcement

The termination of an aversive event, which reinforces the behavior that preceded it.

Escape

A type of behavior or response aimed at getting away from an unpleasant or aversive situation.