Answer:
<em>The skydiver needs 0.71 seconds to reach 7 m/s</em>
Explanation:
<u>Free Fall Motion
</u>
When an object is dropped in free air (no friction) from a certain height h, it follows a free-fall motion, whose acceleration is due exclusively to gravity. The speed at a moment t when the object is dropped (from rest) is:
We need to find How long does the skydiver needs to reach 7 m/s. We solve for t
The skydiver needs 0.71 seconds to reach 7 m/s
Answer:
Explanation:
, where 
<em> </em>= avg. velocity, 
= final velocity, and 
= initial velocity.
Answer:
a. 4.733 × 10⁻¹⁹ J = 2.954 eV b i. yes ii. 0.054 eV = 8.651 × 10⁻²¹ J
Explanation:
a. Find the energy of the incident photon.
The energy of the incident photon E = hc/λ where h = Planck's constant = 6.626 × 10⁻³⁴ Js, c = speed of light = 3 × 10⁸ m/s and λ = wavelength of light = 420 nm = 420 × 10⁻⁹ m
Substituting the values of the variables into the equation, we have
E = hc/λ
= 6.626 × 10⁻³⁴ Js × 3 × 10⁸ m/s ÷ 420 × 10⁻⁹ m
= 19.878 × 10⁻²⁶ Jm ÷ 420 × 10⁻⁹ m
= 0.04733 × 10⁻¹⁷ J
= 4.733 × 10⁻¹⁹ J
Since 1 eV = 1.602 × 10⁻¹⁹ J,
4.733 × 10⁻¹⁹ J = 4.733 × 10⁻¹⁹ J × 1 eV/1.602 × 10⁻¹⁹ J = 2.954 eV
b. i. Is this energy enough for an electron to leave the atom
Since E = 2.954 eV is greater than the work function Ф = 2.9 eV, an electron would leave the atom. So, the answer is yes.
ii. What is its maximum energy?
The maximum energy E' = E - Ф = 2.954 - 2.9
= 0.054 eV
= 0.054 × 1 eV
= 0.054 × 1.602 × 10⁻¹⁹ J
= 0.08651 × 10⁻¹⁹ J
= 8.651 × 10⁻²¹ J
The tension in the supporting cable when the cab originally moves downward is 18422.4 N
What is tension?
Tension is described as the pulling force by the means of a three-dimensional object.
Tension might also be described as the action-reaction pair of forces acting at each end of said elements.
Here,
m =combined mass = 1600 kg
s = Displacement of the elevator = 42 m
g = Acceleration due to gravity = 9.81 m/s²
u = Initial velocity = 12 m/s
v = Final velocity = 0
According to the equation of motion:
0 - 12^2 = 2*a*42
a = - 144 / 84
a = - 1.714 m/s^2
Now let's write the equation of the forces acting on the elevator. Taking upward as positive direction:
T-mg = ma
T = m(g-a)
T = 1600 ( 9.8-(-1.74))
T=18422.4 N
Hence,
The tension in the supporting cable when the cab, originally moving downward is 18422.4 N
Learn more about tension here:
<u>brainly.com/question/13772148</u>
#SPJ4
Answer:
a = 0.098 m/s²
Explanation:
The satellite, at any distance from the center of the Earth, is subject to the attractive force due to the Earth, according to the Newton´s Universal Law of gravitation, as follows:
Fg = G*ms*mE / (rse)²
According to Newton´s 2nd Law, neglecting any other force acted upon the satellite, we can write the following equation:
Fg = ms*a = G*ms*mE / (rse)²
⇒ a = G*mE / (rse)² (1)
As the distance between the satellite and the center of the Earth is 10 times the radius of the Earth, replacing this value in (1), we have:
a = G*mE / (10*RE)² = G*mE/(RE)² * (1/100)
but G*mE/(RE)², is just g, the acceleration due to gravity on the surface of the earth, so the gravitational acceleration due to Earth at satellite A, is as follows:
a = g*(1/100) = 0.01*g = 0.098 m/s²
