Answer:
angular acceleration is -0.2063 rad/s²
Explanation:
Given data
mass m = 95.2 kg
radius r = 0.399 m
turning ω = 93 rpm
radial force N = 19.6 N
kinetic coefficient of friction μ = 0.2
to find out
angular acceleration
solution
we know frictional force that is = radial force × kinetic coefficient of friction
frictional force = 19.6 × 0.2
frictional force = 3.92 N
and
we know moment of inertia that is
γ = I ×α = frictional force × r
so
γ = 1/2 mr²α
α = -2f /mr
α = -2(3.92) /95.2 (0.399)
α = - 7.84 / 37.9848 = -0.2063
so angular acceleration is -0.2063 rad/s²
Answer:
0.75 m
Explanation:
Let's call the distance between the bulb and the mirror x.
The bulb and the length of the mirror form a triangle. The mirror and the illuminated area on the floor form a trapezoid. If we extend the lines from the mirror edge to the reflected image of the bulb, we turn that trapezoid into a large triangle. This triangle and the small triangle are similar. So we can say:
x / 0.4 = (3 + x) / 2
Solving for x:
2x = 0.4 (3 + x)
2x = 1.2 + 0.4 x
1.6 x = 1.2
x = 0.75
So the bulb should located no more than 0.75 m from the mirror.
Answer:
F = 351×10³lb
Explanation:
Given the density
ρg = 64.6lb/ft³
Diameter d = 12ft
The tank is horizontally cylindrical. The vertical distance from the top to the bottom of the tank is h = 12ft
The pressure in the tank is
P = ρgh = 64.6 × 12 = 775.2lb/ft²
The force exerted on one end of the tank is therefore F = PA = 775.2 × πd² = 775.2π×12²
F = 351×10³lb.
Answer:
7,546 J
Explanation:
recall that Potential energy is given by
P.E = mgΔh
where m = 70kg (given)
g = 9.8 m/s² (acceleration due to gravity)
Δh = change in height
= distance from top of building to top of car
= height of building - height of car
= (5+8) - 2
= 11m
substituting all these into the equation:
P.E = mgΔh
= 70 x 9.8 x 11
= 7,546 J
