An element's atomic number is 45. How many protons would an atom of this element have?

A 22.6-kg box is being pushed from the bottom to the top of a frictionless ramp. When the box is pushed at a constant velocity, the nonconservative pushing force does 58.0 J of work.

A person hears an echo from the top of a tower, 2.2 seconds after the sound is produced how far away is the tower from the person? Speed of the sound in the air is 332m/s

A double star has two components of equal brightness, each with a magnitude of 8.34. if these stars are so close together that they appear to be one object, what is the apparent magnitude of the combined object

A 25.0 [cm] long spring stands vertically on the ground, with its lower end secured in a base. A brick with mass, 1.5 [kg] is held 40 [cm] directly above the spring and dropped onto the spring. The spring compresses to a length of 17.

The number of significant digits in the mass of a body measuring 4200.0 kg is 2.

How is Electric current able to flow?

In a series circuit, loads which have the same voltage dropped across them will have?.

When a brick is dropped from the roof of a house, it lands on the ground with a speed v. What will the speed at ground level be for an identical brick dropped from a roof twice as high as the first one?

The scientific method begins with recognizing a problem. The recognized problem in this scenario is, "Why is the printer in the office not working?" Choose the hypotheses that are testable and from which an experiment can be formed.

The correctly balanced equation for H2O2 → H2O + O2 is