C liquid at room temperature
Answer:
17.82J
Explanation:
Kinetic energy = 1/2 mv^2
Given
Mass M = 0.45kg
Velocity v = 8.9m/s
Therefore,
K.E. = 1/2 x 0.45 x (8.9)^2
= 1/2 x 0.45 x (8.9 x 8.9)
= 1/2 x 0.45 x 79.21
Multiply through
= 35.6445/2
= 17.82J
The kinetic energy of the ball is 17.82J
Answer: 37.5 kg in 3 s.f.
Explanation:
Answer:
The mechanical advantage of the system is 8
Explanation:
the mechanical advantage measures how much the system multiplies the input force to get the output.
In the given:
The input force (effort) is 20 Newton
The output force (load) is 160 Newton
This means that the mechanical advantage is:
mechanical advantage = load / effort = 160 / 20 = 8
Note that the mechanical advantage is unit-less (has no unit) since it is a ratio between two forces.
Hope this helps :)
Answer:
T = 188.5 s, correct is C
Explanation:
This problem must be worked on using conservation of angular momentum. We define the system as formed by the fan and the paper, as the system is isolated, the moment is conserved
initial instant. Before the crash
L₀ = r m v₀ + I₀ w₀
the angular speed of the fan is zero w₀ = 0
final instant. After the crash
L_f = I₀ w + m r v
L₀ = L_f
m r v₀ = I₀ w + m r v
angular and linear velocity are related
v = r w
w = v / r
m r v₀ = I₀ v / r + m r v
m r v₀ = (I₀ / r + mr) v
v = 
let's calculate
v = 
v = 
v = 0.02 m / s
To calculate the time of a complete revolution we can use the kinematics relations of uniform motion
v = x / T
T = x / v
the distance of a circle with radius r = 0.6 m
x = 2π r
we substitute
T = 2π r / v
let's calculate
T = 2π 0.6/0.02
T = 188.5 s
reduce
t = 188.5 s ( 1 min/60 s) = 3.13 min
correct is C