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You find yourself in the middle of a frozen lake with a surface so slippery $\left({\mathrm{μ}}_{\mathrm{s}}={\mathrm{μ}}_{\mathrm{k}}=0\right)$ you cannot walk. However, you happen to have several rocks in your pocket. The ice is extremely hard. It cannot be chipped, and the rocks slip on it just as much as your feet do. Can you think of a way to get to shore$?$Use pictures, forces, and Newton's laws to explain your reasoning.

A $3000kg$meteorite falls toward the earth. What is the magnitude of the earth’s acceleration just before impact? The earth’s mass is$5.98×{10}^{24}kg$.

Will hanging a magnet in front of the iron cart in the given figure make it go? Explain.

The given figure shows two masses at rest. The string is massless and the pulley is frictionless. The spring scale reads in kg. What is the reading of the scale?

The foot of a $55kg$sprinter is on the ground for $0.25s$while her body accelerates from rest to $2m/s.$

a. Is the friction between her foot and the ground static friction or kinetic friction?

b. What is the magnitude of the friction force?

A steel cable lying flat on the floor drags a $20kg$block across a horizontal, frictionless floor. A $100N$force applied to the cable causes the block to reach a speed of $4m/s$in a distance of $2m.$

What is the mass of the cable?

The figure shows two masses at rest. The string is massless and the pulleys are frictionless. The spring scale reads in kg. What is the reading of the scale?

An $80kg$spacewalking astronaut pushes off a $640kg$satellite, exerting a $100N$force for the role="math" localid="1649256566272" $0.50\text{s}$it takes him to straighten his arms. How far apart are the astronaut and the satellite after $1min.$

The hand in the figure is pushing on the back of block A. Blocks A and B, with $m_b>m_a$are connected by a massless string and slide on a frictionless surface. Is the force of the string on B larger than, smaller than, or equal to the force of the hand on A? Explain.

The sled dog in the figure drags sleds A and B across the snow. The coefficient of friction between the sleds and the snow is $0.10.$If the tension in rope $1$is$150N,$what is the tension in rope $2?$