edima preguntado en Science & MathematicsPhysics · hace 1 década

# Power - (must be answer before 9pm)?

A car with a mass of 1328 kg is coasting in neutral on a straight , level road. It slows down, and its speed as a afunciton of time is given by the equation:

v(t)=26.8 - 0.310t + 0.0210t^2

At time 14.0 s , the speed, as given by the above equation ,is 22.87 m/s.Calculate the power which the engine must deliver(to compensate for air resistance and rolling resistance) in order to maintain that speed.

What I did ...

p=F*v p=ma*v . I did the derivative of V(t) to get a but I got the wrong answer .Also when it says "maintain that speed" that's it mean constant speed, then a would be 0 ?

### 2 respuestas

Relevancia
• hace 1 década
Respuesta preferida

if its maintaining the speed there is 0 velocity... i think, acceletation = gravity. 9.8 m/s but..

• Erika
Lv 4
hace 4 años

Wow, sounds completely like my dad and mom. I moved out, yet to this present day, they swear I "ran away". heavily. My concern become precisely like this yet worse. i become living house schooled, and lived in an exceptionally rural section, so I had very limited social interplay with any people in besides. i did no longer also have a driving force's license. If i needed to choose for a walk down the airborne dirt and dirt street, my mom had to desire approximately it first, and many the time did no longer "hear from God" that it become risk-free. To this present day, I fairly have nightmares that i'm trapped in that living house. I moved out and into yet another buddy from church's living house. in case you could no longer arise with the money for an house, attempt to flow in with a chum till you could artwork extra hours, or get a miles better activity. I have been given by using it, and you will too.

¿Aún tienes preguntas? Pregunta ahora para obtener respuestas.