What is the mass number of a potassium atom that has 20 neutrons

Knowing that greenhouse gases are contributing to climate change, how can we reduce our carbon footprint, particularly in the United States? Could hydrogen fuel replace fossil fuels in the future? Why or why not?

The current in an oscillating LC circuit is zero at a particular moment. Which one of the following statements is true? A) The charge on the capacitor is equal to zero coulombs. B) Charge is moving through the inductor.

The body went 450 meters within 30 seconds of starting the movement. In what time did the first 50 meters go?

What is the width of a slit for which the first minimum is at 45° when the slit is illuminated by a helium-neon laser (λ = 633 nm) ? Hint: The small-angle approximation is not valid at 45°.

Radiation is an example of a transverse wave t or f

In July 2005, NASA's "Deep Impact" mission crashed a 372-kg probe directly onto the surface of the comet Tempel 1, hitting the surface at 37,000 km/h.

What conversion factor is needed to change from kilometres to meters

What does the law of universal gravitation state?

Estimate the smallest possible period of a satellite in a circular orbit around earth. (mass and radius of earth is 5.98 x 1024 kg and 6.37 x 106 m. the universal gravitational constant g = 6.67 x 10-11 n. m2/kg2.)

What happens along a stationary front? a. Cold air rises over warm air. b. The flow of air is neither toward the warm air mass nor toward the cold air mass. c. Air moves so rapidly upward that hurricanes form. d. Wind stops completely.