Answer:
a) 5.61 rad/s
b) 16.83 rad/s
Explanation:
Distance to the floor = 79cm = 0.79m
Rotation is <1 revolution
The toast will rotate at an angular speed that is constant while it falls. The toast will also be falling with constant acceleration due to gravity. Using equation of motion, which is
S = ut + 1/2gt²
S = 0 + 1/2gt²
S = gt², where, S = d
0.79 = 9.81t²
t² = 0.79/9.81
t² = 0.081
t = 0.28s
As the toast is accidentally pushed, it rotates as it falls. It will be landing on its edges when and if it hits the ground. The smallest angle here would then be 1/4 of the revolution. This is also the smallest angular speed.
ω(min) = ΔΦ revolution /Δt
ω(min) = 1/4 * 2π / 0.28
ω(min) = 0.5π/0.28
ω(min) = 5.61 rad/s
Since 1/4 of revolution is the minimum angle, the remaining(3/4), is the maximum angle. Thus
ω(max) = 3/4 * 2π / 0.28
ω(max) = 0.75 * 2π / 0.28
ω(max) = 16.83 rad/s
Answer:
the coefficient of Kinetic friction between the tires and road is 0.38
Option A) .38 is the correct answer
Explanation:
Given that;
final velocity v = 0
initial velocity u = 15m/s
time taken t = 4 s
acceleration a = ?
from the equation of motion
v = u + at
we substitute
0 = 15 + a × 4
acceleration a = -15/4 = - 3.75 m/s²
the negative sign tells us that its a deacceleration so the sign can be ignored.
Deacceleration due to friction a = μ × g
we substitute
3.75 = μ × 9.8
μ = 3.75 / 9.8 = 0.3826 ≈ 0.38
Therefore the coefficient of Kinetic friction between the tires and road is 0.38
Option A) .38 is the correct answer
Answer:
C. hyperbola
Explanation:
From Boyle's law:
PV = k, where k is a constant
Solving for P:
P = k / V
At first glance, this equation doesn't fit any of the options. But when you graph it, you can see that it's actually a <em>rotated</em> hyperbola.
