Answer:
a) 600 meters
b) between 0 and 10 seconds, and between 30 and 40 seconds.
c) the average of the magnitude of the velocity function is 15 m/s
Explanation:
a) In order to find the magnitude of the car's displacement in 40 seconds,we need to find the area under the curve (integral of the depicted velocity function) between 0 and 40 seconds. Since the area is that of a trapezoid, we can calculate it directly from geometry:
![Area \,\,Trapezoid=(\left[B+b]\,(H/2)\\displacement= \left[(40-0)+(30-10)\right] \,(20/2)=600\,\,m](https://tex.z-dn.net/?f=Area%20%5C%2C%5C%2CTrapezoid%3D%28%5Cleft%5BB%2Bb%5D%5C%2C%28H%2F2%29%5C%5Cdisplacement%3D%20%5Cleft%5B%2840-0%29%2B%2830-10%29%5Cright%5D%20%5C%2C%2820%2F2%29%3D600%5C%2C%5C%2Cm)
b) The car is accelerating when the velocity is changing, so we see that the velocity is changing (increasing) between 0 and 10 seconds, and we also see the velocity decreasing between 30 and 40 seconds.
Notice that between 10 and 30 seconds the velocity is constant (doesn't change) of magnitude 20 m/s, so in this section of the trip there is NO acceleration.
c) To calculate the average of a function that is changing over time, we do it through calculus, using the formula for average of a function:
Notice that the limits of integration for our case are 0 and 40 seconds, and that we have already calculated the area under the velocity function (the integral) in step a), so the average velocity becomes:
The main reason why bells are made up of metals instead of wood is because metal is much more dense than wood, meaning that it resonates at much stronger frequencies. Wood has far too much air in it to make loud noises when struck.
I believe you forgot to add the choices. I will tell you some of the characteristics of mixtures and I hope you find one of them in the choices you have.
A mixture is a physical combination between two or more elements. No chemical reaction is involved in the formation of mixtures.
The components of the mixture can be separated using physical methods such as filtration, boiling and condensation.
Examples of mixtures include mixture of sugar and water or mixture of salt and sugar.
Answer:
T=13.72N
Explanation:
The tension before the ball is released have no angle is in rest at the same axis of the weight so:
∑F=0
Using Newton law in this case the ball is tied so tension before become to swing is
∑F=FN-T=0
Engineers have designed experimental cars that use liquid hydrogen for fuel instead of gasoline. this is an example of Substitution.
Substitution is the process where one thing replaces other for a particular purpose. here liquid hydrogen is replacing the gasoline for fuel in car. hence the correct word to fill is Substitution.
