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Which structure is found in the nucleotides of DNA but not in RNA?

Imagine that a mouse’s DNA molecule results in the codon CCU being to code for proline and a squirrel’s DNA molecule has the codon CCC being the code for proline. (Both of these codons code for proline.) What characteristic accounts for the fact that more than species can code for the same amino acid as another species?

What contains a phosphate group, a 5-carbon sugar, and a nitrogen base?

Two carts collide on a horizontal, frictionless track. Cart A has mass mm and is moving at velocity vv. Cart B is initially at rest and has the same mass. (a) Explain why momentum is conserved during the collision.(b) Describe how you could experimentally determine whether the collision is elastic or inelastic.(c) If the carts stick together after the collision, explain how the total energy of the system changes.

A student places a block on a frictionless incline and releases it from rest. The angle of the incline is increased, and the acceleration of the block is measured. (a) Draw a free-body diagram for the block on the incline.(b) Explain how the angle of the incline affects the acceleration of the block.(c) Describe how you could experimentally determine the gravitational acceleration gg using this setup

A 10.0 kg10.0\, \text{kg} box is pulled across a horizontal surface with a force of 50.0 N50.0\, \text{N} applied at an angle of 30∘30^\circ above the horizontal. The coefficient of kinetic friction is 0.250.25. (a) Draw a free-body diagram for the box.(b) Calculate the normal force acting on the box.(c) Find the net force acting on the box.(d) Determine the acceleration of the box.

A simple pendulum swings back and forth without air resistance. (a) Identify all forms of mechanical energy present in the system and describe how they change during the swing.(b) At what point is the speed of the pendulum the greatest? Justify your answer.(c) Explain why the total mechanical energy of the pendulum remains constant if no non-conservative forces act.

A parallel-plate capacitor is connected to a battery and becomes fully charged. The battery is then disconnected. (a) Explain what happens to the stored energy if the plates are moved farther apart.(b) What happens to the voltage across the plates?(c) Would your answers change if the battery remained connected? Explain why or why not.

A 0.75 m0.75\,\text{m} long wire carries 4.0 A4.0\,\text{A} perpendicular to a 0.60 T0.60\,\text{T} magnetic field.What is the magnetic force?

A square loop of wire is pulled at constant speed out of a uniform magnetic field that points into the page. (a) Describe the direction of the induced current in the loop.(b) What causes this current to be induced?(c) If the speed of the loop is increased, how does that affect the magnitude of the induced current?