Block A, with a Mass of 50 Kg, Rests on a Horizontal

question 69

Multiple Choice

Block A, with a mass of 50 kg, rests on a horizontal table top.The coefficient of static friction is 0.40.A horizontal string is attached to A and passes over a massless, frictionless pulley as shown.The smallest mass m_B of block B, attached to the dangling end, that will start A moving when it is attached to the other end of the string is:

• A)20 kg
• B)30 kg
• C)40 kg
• D)50 kg
• E)70 kg

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Definitions:

Membrane Potential

The difference in electric potential between the interior and the exterior of a biological cell.

Action Potential

A rapid change in electrical potential across a cell's membrane that occurs when a neuron sends information down an axon.

Synapse

The junction between two neurons or a neuron and a muscle or gland cell, where electrical or chemical signals are transmitted.

Presynaptic Cell

A presynaptic cell refers to the neuron that sends a message across the synaptic cleft, releasing neurotransmitters from its axon terminal.