The Arecibo Observatory sent a powerful radio signal to space in 1974. Assume there is an alien civilization located on a planet around Alpha Centauri (distance 4.2 light-years from Earth) and they detect this transmission. They immediately send an invasion force that travels at 10% of the speed of light. What year ON EARTH will the alien invasion force arrive

The slotted link is pinned at o, and as a result of rotation it drives the peg p along the horizontal guide. compute the magnitude of the velocity and acceleration of p along the horizontal guide. compute the magnitudes of the velocity and acceleration of p as a function of θ if θ=(3t) rad, where t is measured in seconds.

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?

Acar travels in reverse. it covers 150 meters in 12 seconds what is the velocity of the car what is the speed of the car