Answer:
4.38 km
Explanation:
Volume of oil slick, V = Area of oil slick, A × thickness of 1 molecule, d'
Since the oil slick spreads out in a circular area, it has the area of a circle.
So, V = πd²/4 × d'
d² = 4V/πd'
d = 2√(V/πd') where d = diameter of oil slick.
Since V = 3000 cm³ = 3000 × 10⁻⁶ m³ = 3 × 10⁻³ m³ and d' = 2 × 10⁻¹⁰ m
So, d = 2√(3 × 10⁻³ m³/(π × 2 × 10⁻¹⁰ m))
= 2√(3 × 10⁻³ m³/(6.283 × 10⁻¹⁰ m))
= 2√(0.477 × 10⁷ m²) = 2√(4.775 × 10⁶ m²)
= 2 × 2.19 × 10³ m
= 4.38 × 10³ m
= 4.38 km
Answer:
v = 2.22 m/s
Explanation:
First we apply the second equation of motion to the vertical motion of the body:
s = Vi t + (1/2)gt²
where,
s = y = vertical distance covered = 200 m - 100 m = 100 m
Vi = V₀y = Vertical Component of Initial Velocity = 0 m/s (because spider man jumps horizontally, thus his velocity has no vertical component initially)
t = Time Taken to Land on 100 m high building = ?
g = 9.8 m/s²
Therefore,
100 m = (0 m/s)t + (0.5)(9.8 m/s²)t²
t² = (100 m)/(4.9 m/s²)
t = √(20.4 s²)
t = 4.5 s
Now, we analyze the horizontal motion. Neglecting air friction, the horizontal motion is uniform with uniform velocity. Therefore,
s = vt
where,
s = x = horizontal distance covered = 10 m
v = V₀ₓ = Horizontal Component of Initial Velocity = Initial Velocity = ?
Therefore,
10 m = v(4.5 s)
v = 10 m/4.5 s
<u>v = 2.22 m/s</u>
The answer is B because I took the test and had the question
Answer:
The angle of incidence is 
Explanation:
The diagram for this question is shown on the first uploaded image
From the question we are told that
The distance between the mirror and the wall is 
The height of the above the mirror is 
Generally the angle which the reflected ray make with the mirror is mathematically evaluated as
substituting values
From the diagram we can deduce that the angle of incidence is
So 
Answer: X = 52,314.12 N
Explanation: Let X be the force the feet of the athlete exerts on the floor.
According to newton's third law of motion the floor gives an upward reaction based on the weight of the athlete and the barbell which is known as the normal reaction ( based on the mass of the athlete and the barbell)
Mass of athlete = 87kg, mass of barbell = 600/ hence total normal reaction from the floor = 87* 61.22/ 9.8 *9.8 = 52,200N.
The athlete lifts the barbell from rest thus making it initial velocity u=0, distance covered = S = 0.65m and the time taken = 1.3s
The acceleration of the barbell is gotten by using the equation of constant acceleration motion
S= ut + 1/2at²
But u = 0
S = 1/2at²
0.65 = 1/2 *a (1.3)²
0.65 = 1.69 * a/2
0.65 * 2 = 1.69 * a
a = 0.65 * 2/ 1.69
a = 0.77m/s²
According to newton's second law of motion
Resultant force = mass * acceleration
And resultant force in this case is
X - 52,200 = (87 + 61.22) * 0.77
X - 52,200 = 148.22 * 0.77
X - 52, 200 = 114.132
X = 114.132 + 52,200
X = 52,314.12 N
