Correct question:
Manny walked a total of 3 miles. The reference point used to calculate the total distance that he walked was the same as the ending point. Which describes where Manny most likely walked?
a. from the bottom of a hill to the top
b. on a circular nature trail
c. on a sidewalk from his house to the mall
d. from the beginning of a straight track to the end
Answer:
b. on a circular nature trail
Explanation:
As it is mentioned that Manny that his reference point from where she started is same as ending point meaning that she moved in a circular path making point B correct answer.
Answer: a) 10.4km
b) 0.62h
C) 17km/h
d) 9.1km/h
Explanation:
A) suppose you move in the positive direction of an x axis, from a first position of x1 = 0 to a second position of x2 at the station. That second position must be at x2 = 8.4 km + 2.0 km = 10.4 km.
B) time interval Dtwlk (= 0.50 h), but we don't know the driving time interval Dt/dr. However, we know that for the drive the displacement Dx/dr is 8.4 km and the average velocity vavg,dr is 70 km/h.
This average velocity is the ratio of the displacement for the drive to the time interval for the drive:
dv = dx/ dt
dt = dx/dv = 8.4/70 = 0.12h
t = ti + two
t = 0.12 + 0.50 = 0.62h
C) avg speed for the entire trip is the ratio of the displacement of 10.4 km for the entire trip to the time interval of 0.62 h for the entire trip.
Avg v = distance/time
10.4/0.62 = 16.8km/h
D) average speed is the ratio of the total distance you move to the total time interval you take to make that move. The total distance is 8.4 km + 2.0 km + 2.0 km = 12.4 km. The total time interval is 0.12 h + 0.50 h + 0.75 h = 1.37 h.
Avg speed = 12.4/1.37 = 9.1km/h
Answer:
Explanation:
a )
Time period T = 1/3 s
angular velocity = 2π / T
= 2 x 3.14 x 3
ω = 18.84 radian / s
b )
Applying conservation of angular momentum
I₁ ω₁ = I₂ ω₂
I₁ / I₂ = ω₂ / ω₁
2 = ω₂ / ω
ω₂ = 2 ω
c )
(KE)initial = 1/2 I₁ ω²
(KE)final = 1/2 I₂ ω₂²
= 1/2 (I₁ / 2) (2ω)²
= I₁ ω²
c )
Change in rotational kinetic energy
= I₁ ω² - 1/2 I₁ ω²
= + 1/2 I₁ ω²
d )
This energy comes from the work done by centripetal force which is increased to increase the speed of rotation.
Straight lines is my best answer
Answer:
Kinetic energy of an object can't be greater than potential energy.
Explanation:
This is due to the reason that some of the energy is lost in the form of friction, heat energy, light energy etc. For example, a ball bounces to a height h in its first bounce.