Radium-214 decays in an alpha decay.

a. what is the mass number of the daughter isotope

How might solar sails be used on Earth?

Explain why some solar eclipses are total and some are annular.

Which best describes the relationship between the frequency, wavelength, and speed of a wave as the wave travels through different media

A string is stretched between a fixed support and a pulley a distance 111 cm apart. The tension on the string is controlled by a weight hanging from the string below the pulley. An electomechnical vibrator is used to vibrate the string at 120 Hz.

A bus and a car have an inelastic head-on collision. The bus has a mass of 1.5 * 10^3 kilograms and an initial velocity of + 20 meters/second. The car has a mass of 9.5 * 10^2 kilograms and an initial velocity of - 26 meters/second.

A car is moving with a speed of 22 m/s. The driver then brakes, and the car comes to a halt after 6.5 s. What is the distance covered by the car after the driver brakes, until it comes to a stop? A) 36 m B) 72 m C) 140 m D) 210 m

Which of the following best explains why an explosive charge in a cannon can cause a cannonball to fly out of the cannon with a high velocity? A. because chemical potential energy can convert to gravitational potential energy B.

Distance divided by time what is velocity

The decay constant of a radioactive nuclide is 4.6 x 10^-3 s^-1. What is the half-life of the nuclide? 2.5 min 2.0 min 1.4 min 3.6 min 3.1 min

A furlong is an old british unit of length equal to 0.125 mi, derived from the length of a furrow in an acre of ploughed land. a fortnight is a unit of time corresponding to two weeks, or 14 days and nights.