1. Intro to Physics Units

The doubly charged ion N²⁺ is formed by removing two electrons from a nitrogen atom. What is the ground-state electron configuration for the N²⁺ ion?

The age of the universe is thought to be about 14 billion years. Assuming two significant figures, write this in powers of 10 in years.

Determine the percent uncertainty in θ, and in sin θ, when θ = 75.0° ± 0.5°.

If you walked north along one of Earth's lines of longitude until you had changed latitude by 1 minute of arc (there are 60 minutes per degree), how far would you have walked (in miles)? This distance is a nautical mile (page 7).

A high-energy beam of alpha particles collides with a stationary helium gas target. What must the total energy of a beam particle be if the available energy in the collision is $16.0$ GeV?

A force is applied to a particle along its direction of motion. At what speed is the magnitude of force required to produce a given acceleration twice as great as the force required to produce the same acceleration when the particle is at rest? Express your answer in terms of the speed of light.

A laser used to weld detached retinas emits light with a wavelength of $652$ nm in pulses that are $20.0$ ms in duration. The average power during each pulse is $0.600$ W. How much energy is in each pulse in joules? In electron volts?

The most common isotope of uranium, ${}_{92}^{238}U$, has atomic mass $238.050788$ u. Calculate (a) the mass defect; (b) the binding energy (in MeV); (c) the binding energy per nucleon.

What is the speed of a proton that has total energy $1000$ GeV?

Global positioning satellites (GPS) can be used to determine your position with great accuracy. If one of the satellites is 20,000 km from you, and you want to know your position to ±2 m, what percent uncertainty in the distance is required? How many significant figures are needed in the distance?

Rewrite 0.00016 kg in scientific notation.

The photoelectric work function of potassium is $2.3$ eV. If light that has a wavelength of $190$ nm falls on potassium, find the kinetic energy, in electron volts, of the most energetic electrons ejected.

"(II) A typical atom has a diameter of about 1.0 x 10^-10 m. Approximately how many atoms are along a 1.0-cm line, assuming they just touch?"

Relativistic Baseball. Calculate the magnitude of the force required to give a 0.145 kg baseball an acceleration a = 1.00 m/s² in the direction of the baseball's initial velocity when this velocity has a magnitude of (a) 10.0 m/s; (c) 0.990c.

Pure germanium has a band gap of $0.67$ eV. The Fermi energy is in the middle of the gap. For temperatures of $250$ K, $300$ K, and $350$ K, calculate the probability $f\left(E\right)$ that a state at the bottom of the conduction band is occupied.