Aremote-controlled car is moving in a vacant parking lot. the velocity of the car as a function of time is given by υ⃗ =[5.00m/s−(0.0180m/s3)t2]i^ + [2.00m/s+(0.550m/s2)t]j^.
a. what is the magnitude of the acceleration of the car at t = 6.23 s ?
i already know that i need to use the derivative of the velocity equation given but i don't know what to do from there.

Current 1 of 8.4 a runs for 240 seconds and then stops. current 2 is 10.5 a. how long does current 2 have to un to deliver the same amount of charge as current 1? 88.28 192 s 2016 s 21,000 s

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

The electric potential v is constant everywhere within a certain region of space. which statement below is true? the choices are: the electric field is also constant (but not zero) within the region. a charged particle placed within the region will experience an electric force. the electric field is zero everywhere within the region. the electric field varies from place to place within the region.