Answer:
500km per hour
Explanation:
if in 2 hours the airplane flies 1000 km then 1000 divided by 2 is 500km per hour.
Answer:
Friction between the box and the floor is 25N to the left.
Explanation:
According to Newton's second law of motion, the net force acting on an object is equal to the produce between the object's mass and its acceleration:
where
m is the mass of the object
a is its acceleration
In this problem, we have two forces acting on the object:
- The applied force, F = 25 N, to the right
- The force of friction 
, opposing the motion of the box, so to the left
So we can write the net force as
Also, we know that the box is moving at constant speed: this means its acceleration is zero, so
Therefore
WHich means:
And therefore,
which means that the force of friction is also 25 N.
<h2>Movement of Continents</h2>
Explanation:
- Alfred Wegener was a German astronomer who proposed the "continental drift" hypothesis in 1910.
- Alfred Wegener was not able to explain the movements of the continent in how and in which way they are moved.
- He failed in an attempt to explain with the use of tides made the theory undefinable fully.
- Also, the major problem with Wegener's theory of Continental Drift was that there was no proper explanation of a mechanism.
Answer:
r = 2161.9 m
Explanation:
Aerodynamic lift(L) is perpendicular to the wing, which is tilted 40 degrees to the horizontal.
Since the plane is moving in a horizontal circle, the vertical component of the lift must cancel the weight W of the airplane, but the horizontal component is the centripetal force that keeps it in a circle.
L is perpendicular to wing at angle θ with respect to horizontal
Thus,
Vertical component of lift is:
L cosθ = W = mg
Thus, m = L cosθ / g - - - - (eq1)
Horizontal component of lift is:
L sinθ = centripetal force = mv² / r - - - - (eq2)
Combining equations 1 and 2,we have;
L sinθ = (L cosθ / g)(v² / r)
L cancels out on both sides to give;
tanθ = v²/ rg
r = v² / (g tanθ)
We are given;
velocity; v = 480 km/hr = 480 x 10/36 = 133.33 m/s
r = 133.33²/[(9.8) tan(40)] = 2161.9 m
Answer:
μ = 0.375
Explanation:
F = Applied force on the trash can = 75 N
W = weight of the trash can = 200 N
f = frictional force acting on trash can
Since the trash can moves at constant speed, force equation for the motion of can is given as
F - f = 0
75 - f = 0
f = 75 N
μ = Coefficient of friction
frictional force is given as
f = μ W
75 = μ (200)
μ = 0.375
