1. What is the best way to determine levelness? A.See if the Acceleration versus
ID: 1268660 • Letter: 1
Question
1. What is the best way to determine levelness?
A.See if the Acceleration versus Time for both directions are both zero.
B.Plot the Acceleration versus Time for one direction and acceleration should be zero.
C.Plot Position versus Time and compare the linear fit from each direction of travel; slopes should be equal.
D.Plot Position versus Time and compare the linear fit from each direction of travel; slopes should be equal but opposite.
E.Plot Velocity versus Time for both directions; slopes should be equal.
F.See if slope of Velocity versus Time for both directions are equal but opposite.
2. In chronological order, what happens to the kinetic, potential, and total energy of the cart for one half cycle. The half cycle starts just after you have pushed the cart. The half cycle finishes just when the cart stops at the height of its motion. Remember, this is about the cart's mechanical energy.
A.Kinetic stays constant because the cart is moving.
Potential starts out high because it has motion at the beginning and then goes to zero a the top since it stops.
Total Energy goes down because the cart is slowing down as it climbs the incline.
B.Kinetic goes from zero to maximum (at the highest point of the incline.)
Potential goes from maximum to zero since the cart has stopped.
Total Energy stays "the same," but decreases slightly due to friction.
C.Kinetic goes from zero to maximum (at the highest point of the incline.)
Potential goes from maximum to zero since the cart has stopped.
Total Energy rises as the cart gains altitude on the incline.
D.Kinetic goes from maximum to zero (at the highest point of the incline.)
Potential goes from zero to a maximum slightly less than Kinetic's maximum.
Total Energy rises as the cart gains altitude on the incline.
E.Kinetic goes from maximum to zero (at the highest point of the incline.)
Potential goes from zero to a maximum slightly less than Kinetic's maximum.
Total Energy stays the same, but decreases slightly due to friction.
3. What word (four letters long that starts with a w) describes the transfer of potential energy into kinetic energy?
(Use all lower case.)
4. Which situation has the greatest magnitude of net force along incline? (By magnitude we mean |F|.)
A.the net force is always the same for an incline, f = mgsin?
B.the net force is always the same for an incline, f = mgcos?
C.when the cart is going downhill
D.when the cart is at rest
E.when the cart is going uphill
5. What are the units for energy?
A.Joule
B.kg m2s-2
C.None of these three units works.
D.N m
E.All three units described here are valid for Energy.
6. Let's say you measure an average acceleration to be 0.4028 ms-2.
What is the height (in centimeters) of the riser block?
Assume the legs of the track span 1.0000 m and that there is neither friction nor drag. Also assume the block is under one of the legs.
cm
Use three significant figures or N/A if not enough information is given.
7. What is the equation used to teach DataStudio the potential energy?
Use variables and type exactly like you should have in DataStudio.
8. You have a level track. You push a cart with mass = 0.74[kg].
You measure the initial velocity to be 0.71[m s-1].
2 seconds later, you measure the velocity to be 0.532[m s-1].
What is the work (reported in mJ) that friction did on the cart?
work = [mJ]
Use three sig. figs. or N/A if not enough information is given, such as change in position!
Remember, that if the system gains energy, then positive work is done;
otherwise the system loses energy ? work done on system < 0.
9. You have a different system of unknown cart mass upon a level surface. The cart travels 165 [cm] in an unknown time period. The change in Kinetic Energy is -0.081798 [J]. What is the force of friction measured in Newtons?
[N]
Use three sig. figs. or N/A if not enough information is given, such as time, and mass! Don't worry about the sign of friction.
Explanation / Answer
1) F.See if slope of Velocity versus Time for both directions are equal but opposite.
2)E.Kinetic goes from maximum to zero (at the highest point of the incline.)
Potential goes from zero to a maximum slightly less than Kinetic's maximum.
Total Energy stays the same, but decreases slightly due to friction.
3) work
4)D.when the cart is at rest
5)E.All three units described here are valid for Energy.
6)(accelgrav)(1.0m)/(9.8) = 3.9984
7)Potential energy is calculated by the formula: PE = mgh where, PE = Energy (in Joules) m = mass (in kilograms) g = gravitational acceleration of the earth (9.8 m/sec2) h = height above earth's surface (in meters) PE = mgh
8)a = v-u / t = (0.532 - 0.710)/2 = 0.089ms-2
S = ut + at2/2 = 0.71*2 - (0.089*4)/2 = 1.42 - 0.098 = 1.322
Work done by friction = m*a*S = 0.74*0.089*1.322 =0.117117 J = 87.067 mJ
9)ake the change in kinetic energy given in the problem and divide by the distance in the problem using the correct units. If the answer is in Newtons change your distance given in cm to the distance in meters before dividing.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.