21. Which of the equations is balanced?

A) 2Li2O + H2O ⇒ 2LiOH

B) 3Fe + 3O2 ⇒ 2Fe2O3

C) 2N2 + O2 ⇒ 3N2O

D) 3Mg + N2 ⇒ Mg3N2

Using a map for trip planning can make driving

How do you calculate the work done when lifting an object?

Intermolecular forces hold

A young boy of mass m = 25 kg sits on a coiled spring that has been compressed to a length 0.4 m shorter than its uncompressed length and then held at this length. Suddenly the spring is released, and the boy flies vertically into the air.

Compare the surface area-to-volume ratios of the earth and venus.

3/129 A 175-lb pole vaulter carrying a uniform 16-ft, 10-lb pole approaches the jump with a velocity v and manages to barely clear the bar set at a height of 18 ft. As he clears the bar, his velocity and that of the pole are essentially zero.

A few years ago, Serena Williams dived to hit a tennis ball right after it bounced off the ground. The ball bounced on the ground 10.3 m from the net, and after Serena hit the ball it flew over the 0.

A force of 1.25x103N is required to lift an object that is under the influence of an acceleration due to gravity of 7.86ft/sec2. What is the object's mass in kilograms?

Which of these events is an example of the Doppler shift? The amplitude of a wave on a string increases as the frequency decreases. The amplitude of sound from a tuning fork decreases due to damping.

One disadvantage of this type of power is that it still pollutes the air. biomass geothermal power hydropower solar power You want to create a new warming appliance that is safe.