A rocket powered car is set inside a circular track and ignited. Pressure sensors on the wall of the track measure the centripetal acceleration of the car as a function of time to be c()=(1 m/s^6)^4+(14 m/s^4)^2+(49 m/s^2)

If the radius of the track is 3.78 m, what is the tangential acceleration of the rocket car at =4.51 s?

15.3 cos 65 degrees trig

a and b sometimes have a positive value

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west