a body starts from rest and accelerates uniformly at 5ms‐2. Calculate the time taken by the body to cover a distance of 1km

What would the difference of spectral lines emitted by hydrogen gas in distant galaxies which is normally found at a wavelength of 21 cm on earth, be observed at 21.1 centimeters?

Spend time observing or thinking about events that involve matter and energy. which events can you explain? which events can’t you explain?

3. on your graph, the data points between the black squares are data for elements with atomic numbers 3 through 9. locate these elements on your periodic table. what term or description would you use to identify these elements with respect to the periodic table?