The motion of an object through the air does not affect by its mass. The rate of fall of objects does not depend upon the mass.
Free fall is a motion of a body in which gravity is the only force acting upon it. An object moving upwards might not be considered to be falling. But if the object is under the effect of the force of gravity, it is said to be in free fall.
Free fall is a type of motion in which the force acting upon an object is only gravity. Objects are not encountering a significant force of airresistance as they are only falling under the sole influence of gravity. All objects under such conditions will fall with the same rate of acceleration, regardless of their masses.
As an object falls through the air, have gone through some degree of air resistance. Air resistance is the collisions of the object's leading surface with molecules present in the air. The two most common factors that have a direct effect on the amount of air resistance are the cross-sectional area of the object and the speed of the object.
Learn more about free-fall motion, here:
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Answer:
9.93 MPa
Explanation:
Given:
- mass of the man = 68.4 kg
- Deflection dx = 5.2 cm
- thickness of plank t = 2.0 cm
- width of plank w = 13.0 cm
- Length subtended L = 2.0 m
Find:
Shear Modulus of Elasticity S :
S = shear stress / shear strain
Shear stress = F / A
Shear stress = 68.4*9.81 / 0.02*0.13
Shear stress = 258078.4615 Pa
Shear strain = dx / L
Shear Strain = 0.052 / 2
Shear Strain = 0.026
Hence,
S = 258078.4615 / 0.026
S = 9.93 MPa
Answer:
D=1.54489 m
Explanation:
Given data
S=6.10 mm= 0.0061 m
To find
Depth of lake
Solution
To find the depth of lake first we need to find the initial time ball takes to hit the water.To get the value of time use below equation
So ball takes 0.035sec to hit the water
As we have found time Now we need to find the final velocity of ball when it enters the lake.So final velocity is given as
Since there are (4.50-0.035) seconds left for (ball) it to reach the bottom of the lake
So the depth of lake given as:
Answer: d = 1.54m
The depth of the lake is 1.54m
Explanation:
The final velocity of the ball just before it hit the water can be derived using the equation below;
v^2 = u^2 + 2as ......1
Where ;
v is the final velocity
u is the initial velocity
a is the acceleration
s is the distance travelled.
Since the initial velocity is zero, and the acceleration is due to gravity, the equation becomes:
v^2 = 2gs
v = √2gs ......2
g = 9.8m/s^2
s = 6.10mm = 0.0061m
substituting into equation 2
v = √(2 × 9.8× 0.0061)
v = 0.346m/s
The time taken for the ball to hit water from the time of release can be given as:
d = ut + 0.5gt^2
Since u = 0
d = 0.5gt^2
Making t the subject of formula.
t = √(2d/g)
t = √( 2×0.0061/9.8)
t = 0.035s
The time taken for the ball to reach the bottom of the lake from the when it hits water is:
t2 = 4.5s - 0.035s = 4.465s
And since the ball falls for 4.465s to the bottom of the lake at the same velocity as v = 0.346m/s. The depth of the lake can be calculated as;
depth d = velocity × time = 0.346m/s × 4.465s
d = 1.54m
The depth of the lake is 1.54m
Explanation:
For Part (a)
Since the apparent wavelength decreases hence galaxy moving towards the stationary observer.
Δλ/λ=v/c
For Part (b)
Since the apparent wavelength increases hence galaxy moving towards the stationary observer.
Δλ/λ=v/c
How far does the car move during the 2.52 s?
How long does it take the car to come to a complete stop?
Answer:
19.1 m/s
58.1 m
8.60 s
Explanation:
Take north to be positive and south to be negative.
Use Newton's second law to find the acceleration.
∑F = ma
-7850 N = (2500 kg) a
a = -3.14 m/s²
Given:
v₀ = 27.0 m/s
a = -3.14 m/s²
Find: v given t = 2.52 s
v = at + v₀
v = (-3.14 m/s²) (2.52 s) + 27.0 m/s
v = 19.1 m/s
Find: Δx given t = 2.52 s
Δx = v₀ t + ½ at²
Δx = (27.0 m/s) (2.52 s) + ½ (-3.14 m/s²) (2.52 s)²
Δx = 58.1 m
Find: t given v = 0 m/s
v = at + v₀
0 m/s = (-3.14 m/s²) t + 27.0 m/s
t = 8.60 s
Answer:
475 N/C
Explanation:
As we know that, the electric field in parallel plate capacitor is same (constant) throughout. And is potential gradient.
So, Electric field is given by
Electric field = potential gradient
Here, the potential change is 3.8V and the distance from negative plate to positive plate is 1.6 cm. The potential from negative plate to the center is (1.6/2)cm i.e., 0.8 cm.
But we have to take distance in SI units So, distance=
So, Electric field is
So, electric field is 475 Volts per meter.
Note : Also we can say 475 Newtons per coulomb
Find the radius and period of the orbit.
Answer:
r = 2,026 10⁹ m and T = 2.027 10⁴ s
Explanation:
For this exercise let's use Newton's second law
F = m a
where the force is electric
F =
Acceleration is centripetal
a = v² / r
we substitute
r = (1)
let's look for the charge in the insulating sphere
ρ = q₂ / V
q₂ = ρ V
the volume of the sphere is
v = 4/3 π r³
we substitute
q₂ = ρ π r³
q₂ = 3 10⁻⁹ π 4³
q₂ = 8.04 10⁻⁷ C
let's calculate the radius with equation 1
r = 9 10⁹ 1.6 10⁻¹⁹ 8.04 10⁻⁷ /(9.1 10⁻³¹ 628 10³)
r = 2,026 10⁹ m
this is the radius of the electron orbit around the charged sphere.
Since the orbit is circulating, the speed (speed modulus) is constant, we can use the uniform motion ratio
v = x / t
the distance traveled in a circle is
x = 2π r
In this case, time is the period
v = 2π r /T
T = 2π r /v
let's calculate
T = 2π 2,026 10⁹/628 103
T = 2.027 10⁴ s