Answer:
Juan and Kuri complete one revolution in the same time, but Juan travels a shorter distance and has a lower speed.
Explanation:
Since Juan is closer to the center and Kuri is away from the center so we can say that Juan will move smaller distance in one complete revolution
As we know that the distance moved in one revolution is given as
also the time period of revolution for both will remain same as they move with the time period of carousel
Now we can say that the speed is given as
so Juan will have less tangential speed. so correct answer will be
Juan and Kuri complete one revolution in the same time, but Juan travels a shorter distance and has a lower speed.
Answer:
D) the second at the doorknob
Explanation:
The torque exerted by a force is given by:
where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation
is the angle between the direction of the force and d
In this problem, we have:
- Two forces of equal magnitude F
- Both forces are perpendicular to the door, so 
- The first force is exerted at the midpoint of the door, while the 2nd force is applied at the doorknob. This means that d is the larger for the 2nd force
--> therefore, the 2nd force exerts a greater torque
Answer:
the time needed for her to close the door is 1.36 s.
Explanation:
given information:
Force, F = 220 N
width, r = 1.40 m
weight, W = 790 N
height, h = 3.00 m
angle, θ = 90° = π/2
to find the times needed to close the door we can use the following equation
θ = ω₀t + 1/2 αt²
where
θ = angle
ω = angular velocity
α = angular acceleration
t = time
in this case, the angular velocity is zero. thus,
θ = 1/2 αt²
now, we can find the angular speed by using the torque formula
τ = I α
where
τ = torque
I = Inertia
we know that
τ = F r
and
I = 1/3 mr²
so,
τ = I α
F r = 1/3 mr² α
α = 3 F/mr
= 3 F/(w/g)r
= 3 (220)/(790/9.8) 1.4
= 5.85 rad/s²
θ = 1/2 αt²
π/2 = 1/2 5.85 t²
t = 1.36 s
Answer: 60.56
Explanation: Just multiply 3.785 by 16.
