Why was basketball invented?
When light is directed on a metal surface, the kinetic energies of the photoelectrons a) are random b) vary with the frequency of the light c) vary with the intensity of the light d) vary with the speed of the light
Answer:
b) vary with the frequency of the light
Explanation:
The phone electric effect can be expressed as
K.E=(hv -W•)
Where K.E is the Kinectic energy
W• = work function of the metal
ν =frequency of the radiation
h = Planck's constat
Then, we can see that K.E is proportional linearly to "v" in the equation above.
Therefore, When light is directed on a metal surface, the kinetic energies of the photoelectrons vary with the frequency of the light
Harry Styles fires a T-shirt cannon horizontally off a stage 10 meters high, with an
initial velocity in the x-direction of 5 meters per second. How far away from the
stage should you stand to be able to catch the t-shirt?
Answer:
7.15 m
Explanation:
From the question given above, the following data were obtained:
Height (h) = 10 m
Initial velocity (u) = 5 m/s
Horizontal distance (s) =?
Next, we shall determine the time taken for the shirt to get to the ground. This can be obtained as follow:
Height (h) = 10 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =?
h= ½gt²
10 = ½ × 9.8 × t²
10 = 4.9 × t²
Divide both side by 4.9
t² = 10 / 4.9
t² = 2.04
Take the square root of both side
t = √2.04
t = 1.43 s
Finally, we shall determine the horizontal distance travelled by the shirt. This can be obtained as follow:
Initial velocity (u) = 5 m/s
Time (t) = 1.43 s
Horizontal distance (s) =?
s = ut
s = 5 × 1.43
s = 7.15 m
Thus, the shirt will land at 7.15 m away from the stage. Thus, to catch the shirt, you must be at a point 7.15 m away from the stage.
when it comes to graphs I am no genius lol
Answer:
Option B
Explanation:
Displacement = Area under the velocity-time graph
So to find the displacement of a particle from 7 to 8 seconds we take the triangle and calculate its area.
[tex]Area\ of\ a\ right\ angled\ triangle = \frac{1}{2}*(base)*(height) \\\\Area\ of\ a\ right\ angled\ triangle = \frac{1}{2}*(1)*(3) \\\\Area\ of\ a\ right\ angled\ triangle = 1.5[/tex]
So the displacement is 1.5 meters
I have an uploaded image so you can understand it better hope it helps
A box is sitting stationary on a long level ramp on level ground. The coefficient of static friction is (1.0). One end of the ramp is slowly lifted higher and higher. What is the angle of the ramp with respect to the ground when the box begins slidig?
Answer:
45 degrees
Explanation:
Given that the coefficient of friction, [tex]\mu=1.0[/tex]
Let the angle of the ramp be [tex]\theta[/tex].
The gravitational force acting downward [tex]=mg[/tex]
The normal reaction by the ramp on the box, [tex]N=mg\cos\theta[/tex]
So, the maximum frictional force that can act on the box, [tex]f= \mu N[/tex]
The force along with the plane in the direction of sliding, [tex]F = mg\sin\theta[/tex]
When the box begins sliding, the F must have to overcome the frictional force,f.
So, F=f
[tex]mg\sin\theta=\mu N \\\\mg\sin\theta=\mu mg\cos\theta \\\\\frac {\sin\theta}{\cos\theta}=\mu \\\\\tan\theta=\mu \\\\\theta=\tan^{-1}\mu \\\\[/tex]
Putting the value of \mu, we have
[tex]\theta=\tan^{-1}1[/tex]
[tex]\theta=45[/tex] degrees.
Hence, the angle of the ramp with respect to the ground when the box begins sliding is 45 degrees.
A sky diver with a mass of 80 kg jumps from a plan. They are accelerating at a constant rate due to gravity which is 9.8 m/s2. What is the net Force of the sky diver? Show your work.
Answer:
At terminal velocity, the drag force = mass x g
Explanation:
Force = 80 kg x 9.8 m/s2 = 784 kgm/s2 = 784 N
Question 6 (14 points)
A 3.68 kg object is tied to the end of a cord and whirled in a horizontal circle of radius 881 cm. The object completes 10.8 revolutions every 18.8
s. What is the centripetal acceleration of the object?
Answer:
[tex]a=114\ m/s^2[/tex]
Explanation:
Given that,
Mass of an object, m = 3.68 kg
It is whirled in a horizontal circle of radius 881 cm or 8.81 m
The object completes 10.8 revolutions every 18.8 s.
We need to find the centripetal acceleration of the object. It is given by the formula as follows :
[tex]a=\omega^2 r[/tex] ...(1)
Where [tex]\omega[/tex] is angular velocity
10.8 revolutions = 67.85 rad
[tex]\omega=\dfrac{67.85\ rad}{18.8\ s}\\\\=3.6\ rad/s[/tex]
Put values in equation (1)
[tex]a=3.6^2\times 8.81\\\\a=114\ m/s^2[/tex]
So, the centripetal acceleration of the object is [tex]114\ m/s^2[/tex].
An example of a poor coping mechanism is ?
Answer: A bad, maladaptive, unhealthy or destructive coping mechanism is one where the behavior does not resolve the problem in the long-term and may actually increase the harm. Unhealthy coping strategies may feel like they are having the desired effect in the short term.
Explanation: Yes, it was from google...
In a physics demonstration, two identical balloons (A and B) are propelled across
the room on horizontal guide wires. The motion diagrams (depicting the relative
position of the balloons at time intervals of 0.05 seconds) for these two balloons are
shown below.
Balloon A
Balloon B
Which balloon (A or B) has the greatest acceleration? Explain.
Which balloon (A or B) has the greatest final velocity? Explain.
3. Which of the following is an example of Newtons second law of motion? (2 points)
O Caties skateboard hits a curb and she falls forward onto the grass.
O A tissue and a rock are dropped from a ladder. The rock exerts a greater force when it hits the ground.
A person stands on a chair and pushes down, and the chair pushes upwards on the person.
Tires from a bike push against the road, and the road pushes back.
Answer:b
Explanation: i took the test and b was correct
What best describes the states of nonmetals when they are at room temperature?
Most nonmetals are gaseous, but some are liquid or solid.
All nonmetals are gaseous unless they bond with a metal.
Most nonmetals are solids, but some are gaseous or liquid.
All nonmetals are solid unless they bond with a metal.
Answer:
A.) Most nonmetals are gaseous, but some are liquid or solid
Explanation:
Answer:
a
Explanation:
Which of the following would be an example of mechanical energy?
Elastic Energy, Kinetic Energy, Gravitational Potential Energy
Gravitational Potential Energy, Thermal Energy
Electric Potential Energy, Nuclear Energy, Kinetic Energy
Magnetic Energy, Elastic Potential Energy
Answer:
A) Elastic Energy, Kinetic Energy, and Gravitational Potential Energy
Explanation:
Hope this helps!
How much power will it take to move a 10 kg mass at an acceleration of 2 m/s² a distance of 10 meters in 5 seconds?
Answer:
100 Watts
Explanation:
These equations are needed to work out the answer:
power= work done/ time takenwork done= force* distanceforce= mass* accelerationforce: 10 kg* 2m/s= 20
work done: 20* 10m=200
power: 200/2=100
In physics,
is defined as a change in position over time.
a.distance
b.motion
c.momentum
d.vector
Jake and Amir are both standing on identical skateboards and
perform a physics experiment in which they push off one
another to move. Jake is taller and more massive than Amir. If
Jake pushes with 20 N of force, what force would he feel
backwards away from Amir? F= N
Answer: 20
Explanation:
If Jake pushes with 20 N of force, the force that he would feel backwards away from Amir is 20N
Force simply means the strength or energy that can later the position of an object. Force can also be described as a push or pull.
It should be noted that since Jake pushes with 20 N of force, the force that he would feel backwards away from Amir will be the exact force that was used in pushing.
This will therefore be 20 Newton as well.
Read related link on:
https://brainly.com/question/18038995
As a young boy swings a yo-yo parallel to the ground and above his head, the yo-yo has a centripetal acceleration of 250 m/s2 . If the yo-yo’s string is 0.50 m long, what is the yo-yo’s tangential speed?
Centripetal acceleration ac is the acceleration experienced while in uniform circular motion. It always points toward the center of rotation. It is perpendicular to the linear velocity (tangential speed) v and has the magnitude:
[tex]a_c = \dfrac{v^2}{R}[/tex]
Solving for v:
[tex]v = \sqrt{a_c R} = \sqrt{(250\;m/s^2)(0.50\;m)} = 5\sqrt{5}\;m/s \approx 11.18\;m/s[/tex]
The yo-yo’s tangential speed 11.18 m/sec.
What is speed?The speed of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.
Centripetal acceleration ac is the acceleration experienced while in uniform circular motion. It always points toward the center of rotation. It is perpendicular to the linear velocity (tangential speed) v and has the magnitude:
[tex]a_{c} = v^2/r[/tex]
Solving for v
[tex]v = \sqrt{a_{c}r }[/tex] = 11.18 m/sec
The yo-yo’s tangential speed 11.18 m/sec.
To learn more about speed refer to the link:
brainly.com/question/28224010
#SPJ2
A car’s momentum is p when it is traveling with a velocity of v. If the velocity of that car doubles, what is the new momentum of the car?
Answer:
∆p=(m2v)kg.m/s
Explanation:
∆p=mv where v=2v. hence ∆p=m2v
Answer:
c. 2p
Explanation:
edge 2021
is a tree a living or non living thing?
Answer:
Living thing
Explanation:
Nonliving things do not move by themselves, grow, or reproduce.
Answer:
Living
Explanation:
Unless you cut the tree, making that thang dead- its living
Which of the following has the largest momentum?
a. 5kg bowling ball moving with a velocity of 2m/s
b. A 4kg rock rolling down a hill with a velocity of 3m/s
c. A 200kg rock sitting on top of a hill that is 5m height.
d. 0.0025kg bullet that is moving with a velocity of 200m/s
Answer:
Option b
Explanation:
The formula of momentum is [tex]p=mv[/tex]
where p is the momentum , m is the mass in kg and v is the velocity in m/s, so
a) momentum is
[tex]p=mv\\p=5(2)\\p=10[/tex]
b) momentum is
[tex]p=mv\\p=4(3)\\p=12[/tex]
c) momentum is
here since the rock is sitting on top of a hill which means the object is stationary or in other words the object is at rest, which means if an object is at rest the velocity is 0m/s so momentum is zero of a stationary object because
[tex]p=mv\\p=200(0)\\p=0[/tex]
d) momentum is
[tex]p=mv\\p=0.0025(200)\\p=0.5[/tex]
so the highest momentum is in part b which is 12 so option b is our answer.
Answer:
c
Explanation:
THIS IS SOOO IMPORTANT PLS HELP I’LL GIVE BRAINIEST
Describe the evidence of chemical changes that occurred during the etching process in:
a. your circuit board.
b. the copper chloride etching solution.
Give at least one piece of evidence for parts a & b--> Have at least one full sentence for each answer.
Answer:
Chemical etching is a process of printed circuit board (PCB) manufacturing that provides many advantages over mechanical methods.
Explanation:
There's one! UvU hope this helped in whatever you're in for! <3
Good Luck!
Energy that is stored is called...
Answer:
Potential energy
Explanation:
Potential energy is stored energy and the energy of position––gravitational energy. There are several forms of potential energy. Electrical Energy is the movement of electrical charges. Everything is made of tiny particles called atoms.
- Scientific Forms of Energy_ Stored Energy, Kinetic Energy ...ei.lehigh.edu › learners › energy › readings › energy_basics
How long does it take to run 2000 meters if you run 2 m/s
Answer:
1000 seconds.
Explanation:
How can we use magnetic fields to transport objects from one location to another?
Why might it be important to know your inherited traits passed down by your parents?
Answer:
health factors that could harm you or your offspring
On a sunny summer day, why does a white car with a light-colored interior stay cooler than a black car with a dark-colored interior?
Solar radiation reflects off the lighter colours, away from the car, thus keeping the car cool
Solar radiation is absorbed into the lighter colours, keeping the car cool
Solar radiation is absorbed into the darker colours, keeping the car cool
Solar radiation reflects off the darker colours, away from the car, thus keeping the car cool
Answer: Solar radiation reflects off the lighter colours, away from the car, thus keeping the car cool
Explanation: This is because lighter colors reflect a good amount of radiation while darker colors absorb it. Just like, Antarctica hasn't completely melted because it reflects a lot of the heat that is acting upon it. Or, you notice that you get hotter when you wear a black shirt opposed to a white one.
please help !!!!! I’ll give brainliest !
I think A but I dont really know
Plz do it all plz plz and i will give brainlest and thanks to best answer do it right plz
Answer: Hawk.
Explanation: I dont know for sure, but thats what it looks like to me.
[tex] \frac{1}{(1 - \sqrt{3) {}^{2} } } [/tex]
Answer:
\frac{2+\sqrt{3}}{2}
Explanation:
so we simplify tthe denominator first
[tex](1-\sqrt{3})^2=[/tex][tex]4-2\sqrt{3}[/tex]
so the new fraction is:[tex]\frac{1}{4-2\sqrt{3}}[/tex]
We'll ratinalize the fraction to get: [tex]\frac{2+\sqrt{3}}{2}[/tex]
A 2000 kg minivan runs into a 800 kg car that was at rest at a stop sign and they stick together. If the compact car does not stick to the van but, instead, causes the minivan to come to a complete stop. How fast will the car be going after the collision?
Answer:
v₂ = 2.5 v₁
car leaves at 2.5 times the speed of the minivan
Explanation:
This is an exercise of conservation of the momentum, to solve it we create a system formed by the minivan and the car, therefore during the crash the forces are internal and the momentum is conserved.
Initial instant. Before the crash
p₀ = M v₁+ 0
Final moment. After the crash
[tex]p_{f}[/tex] = M 0 + m v₂
how momentum is conserved
p₀ = p_{f}
M v₁ = m v₂
v₂ = [tex]\frac{M}{m}[/tex] v₁
let's calculate
v₂ = 2000/800 v₁
v₂ = 2.5 v₁
therefore the car leaves at 2.5 times the speed of the minivan
A boat travels at 15 m/s in a direction 45° east of north for an hour. The boat then turns and travels at 18 m/s in a direction 5° north of east for an hour.
Answer:
first one 31
second one 23
Explanation:
on edge ;))