m = mass of the box
N = normal force on the box
f = kinetic frictional force on the box
a = acceleration of the box
μ = coefficient of kinetic friction
perpendicular to incline , force equation is given as
N = mg Cos30 eq-1
kinetic frictional force is given as
f = μ N
using eq-1
f = μ mg Cos30
parallel to incline , force equation is given as
mg Sin30 - f = ma
mg Sin30 - μ mg Cos30 = ma
"m" cancel out
a = g Sin30 - μ g Cos30
inserting the values
1.20 = (9.8) Sin30 - (9.8) Cos30 μ
μ = 0.44
Answer:
1.23453*10^5 is scientific way
Answer:
Explanation:
Let's look at a mathematical representation of this. The equation for tis is just a souped up version of Newton's 2nd Law:
F - f = ma. It an object is moving at a constant speed, the acceleration of that object is 0. That changes this equation to
F = f which states that the applied Force equals the frictional force, choice a.
Explanation:
The total energy of an aircraft flying in the atmosphere can be calculated using equation 1. [2]
E = ½ m v2 + mgh
A Boeing 737-300 has a maximum takeoff weight of 5.65 × 104 kg, a cruise altitude of h = 10,195 m, and cruise speed of 221 m/sec. Inserting these numbers into the above equation, we obtain 7.03 GJ for the energy at cruise conditions. [3] However, the engines mounted onto the wings of the plane are required to provide additional energy per time, power, in order to keep the aircraft flying at a constant altitude and speed
Work is the energy needed to apply a force to move an object a particular distance, where force is parallel to the displacement. Power is the rate at which that work is done.
Answer:
(a) 23 m/s, -4 m/s²
(b) Speed is decreasing.
Explanation:
The velocity of the object is given as:
v(t) = 27 - t²
When t = 2 secs, velocity, v(2) becomes:
v(2) = 27 - (2)²
v(2) = 27 - 4
v(2) = 23 m/s
The acceleration is the first derivative of the velocity, dv/dt:
a(t) = dv(t)/dt = -2t
Acceleration after 2 secs, a(2) is:
a(2) = -2*2
a(2) = -4 m/s²
(b) When velocity and acceleration have opposite signs, it means that the velocity and acceleration are in opposite directions, hence, the object is slowing down.
In other words, the speed is decreasing.
