Hi there!
We can begin by calculating the impulse exerted on the soccer ball:
I = Δp = mΔv
Plug in the given values:
I = 0.45 × 20 = 9 Ns
I = Ft, so:
I/t = F
9/0.1 = 90 N
If a car is at rest, which of the following is correct?
A.not enough information
B.more than 3 forces are acting on the car
C.no force acts on the car
D.The net force on the car is zero
Answer:
D
Unbalanced or net forces acting on the car will cause it to move
The correct answer is option D. The net force on the car is zero.
What forces act on a car at rest?
Since the car is not accelerating, the force of air resistance and the friction force must add to give the exact opposite of the applied force. The net force here would be zero, as well.
When an object is at rest no gravitational force is acting on it?Newton's First Law is the law of inertia. An object with no net forces acting on it which is initially at rest will remain at rest. If it is moving, it will continue to move in a straight line with constant velocity.
Learn more about Newton's First Law here: https://brainly.com/question/11472821
#SPJ2
How many revolutions does the motor shaft turn through between the time when the current is reversed and the instant when the angular velocity is zero
Answer:it equals 0
Explanation:hope this is a good answer
Angular velocity is the ratio of angular displacement to time. Then the number of turns by the shaft is zero.
What is angular velocity?The rate of change of angular displacement is called angular velocity. It is a vector quantity.
We know that the angular velocity formula
[tex]\rm Angular \ velocity = \dfrac{Angular \ displacement}{time}[/tex]
The motor shaft turns through between the time when the current is reversed and the instant when the angular velocity is zero.
Then the number of turns will be
[tex]\rm Number \ of\ turns = Angular \ velocty \times time \\\\Number \ of\ turns = 0 *time \\\\Number \ of\ turns = 0[/tex]
The number of turns by the shaft is zero.
More about the Angular velocity link is given below.
https://brainly.com/question/7359669
A taxi is travelling at 20 m/s. Its driver accelerates with acceleration 5 m/s2 for 4 s. What is its new velocity?
Please find attached photograph for your answer.
Hope it helps.
Do comment if you have any query.
I'LL MARK YOU BRAINLIST!!
ali starts moving his car from rest and accelerates it at 5 m/s^2 over 8 seconds. what is the velocity of ali's car reached by the end of these 8 seconds ?
Explanation:
u=0, v=?, a=5m/s², t=8sec
So, by the formula,
v=u+at
v=0+5×8
v=40m/s.
hope this helps you .
What time is the lunar eclipse tonight in california?
2. Summarize how to use a spring scale to measure a pull and how to use it to apply a push with
a specific force.
If the spring constant is known, the extension or compression of the spring can be used to calculate the applied force (pull or push) on the spring.
According to Hook's law, the force applied to an elastic material is directly proportional to the extension of the material.
The force applied;
F = kx
where;
k is the springThe applied force can be in form of push or pull. A push force can result in compression of the spring while a pull force can result in extension of the spring.
If the spring constant is known, the extension or compression of the spring can be used to calculate the applied force (pull or push) on the spring.
Learn more here:https://brainly.com/question/4404276
Krishna wants to measure the mass and volume of a key. Which tools should she use?
a balance and a beaker of water
a balance and a meter stick
a beaker of water and a ruler
a ruler and a meter stick
Answer:
a balance and a beaker of water
Explanation:
The mass can easily be measured with balance. If you drop the key in a beaker of water, the water inside the beaker will increase and this increases the volume of water that will be equal to volume of key.
negatively charged particles of radiation emitted from the decay of radioactive substances are known as
Answer: beta particles
Explanation:
that's the answer
What average force magnitude is required to stop a 15,000 kg train in 12.1 s if the train is traveling at 86 km/hr
Answer:
Explanation:
Givens
m = 15000 kg
t = 12.1 seconds
vi = 86 km / hr
vf =0
Formula
F = m*a
a = (vf - vi)/ t
vi has to be converted to m/s
86 km/hr [1000 m / 1 km] * [1 hour / 3600 seconds]
86 * 1000 / 3600 = 23.89 m/s
Solution
a = (vf - vi) / t
a = (0 - 23.89)/12.1
a = - 1.97 m/s^2 The minus means that the trains is slowing down.
F = 15000 kg * - 1.97 m/s^2
F = -29615.7 Newtons.
Question 5: A heavy rope is flicked upwards, creating a single pulse in the rope. Make a drawing of the rope and indicate the following in your drawing
a. the direction of motion of the pulse
b. Amplitude
c. Pulse length
d. Position of the rest
Answer:
the direction of motion of the pulse
consider two vectors A and B Where A-B and |A+B|=|A-2B| vector B is directed in the positive x_direction and A makes an angle of 60°above the positive x_axis find magnitude of the two vectors
Answer:
It should be mentioned that an efficient way to work this vector addition problem is with the cosine law for general triangles (and since
a
,
b
and
r
from an isosecles triangle, the angles are easy to figure). However, in the interest of reinforcing the usual systematic approach to vector addition, we note that the angle
b
makes with the +x axis is 30
0
+105
0
=135
0
(a) The x component of
r
x
=(10.0m)cos30
0
+(10.0m)cos135
0
=1.59m
(b) the y component of
r
is r
y
=(10.0m)sin135
0
= 12.1 m.
(c) the magnitude of
r
is r = ∣
r
∣=
(1.59m)
2
+(12.1m)
2
=12.2m
(d) The angle between
r
and the +x direction is tan
−1
[(12.1m)/(1.59m)]=82.5
0
Explanation:
please solve due is today....asap please
Answer:
a)object is in uniform motion
Explanation:
velocity is constant.and a=0
body is in uniform motion.
BRAINLIST PLS
When making a left turn, drive into the intersection, make the turn smoothly and without strain on the engine, braking to about ... to .........mph and stay on the brake until approximately half way into the intersection.
Answer:
whats the question
Explanation:
What would the kinetic energy of a 20kg person running at a velocity of 2.5m/s?
Answer:
62.5 JExplanation:
The kinetic energy of an object can be found by using the formula
[tex]k = \frac{1}{2} m {v}^{2} \\ [/tex]
m is the mass in kg
v is the velocity in m/s
From the question
m = 20 kg
v = 2.5 m/s
From the question we have
[tex]k = \frac{1}{2} \times 20 \times {2.5}^{2} \\ = 10 \times 6.25 \\ = 62.5\: \: \: \: \: \: \: \: \: \: [/tex]
We have the final answer as
62.5 JHope this helps you
Describe the forces that make a bicycle move.
Answer:
this is an example of Newton's Second Law, acceleration happens when a force acts on a mass.
the force that makes the bicycle move is your foot pushing against the pedal
What might be an example of newtons second law of motion
Answer:
Pushing a car and a truck
Explanation:
A galaxy spectrum has a redshift of 70,000 km per second. If the Hubble constant is 70 km per second per Mpc (megaparsec), how far away from us in this galaxy
Using the Hubble law v = H₀d where v = recessional speed = 70,000 km per second H₀ = hubble constant = 70 km/s/Mpc and d = distance of galaxy.
Making d subject of the formula, we have
d = v/H₀
Substituting the values of the variables into the equation, we have
d = v/H₀
d = 70000 km/s/70 km/s/Mpc
d = 1000 Mpc
So, the galaxy is 1000 Mpc away from us.
Learn more about hubble law here:
https://brainly.com/question/18484687
When riding your bike, you come up to a small child who jumps in front of you. You slam on the brakes, and your bike comes to a sliding stop. Which force greatly increases when you lock the brakes and slide
Answer: friction :)
Explanation:
I took the test and got 100%
If a statue is made out of wood, which of these words correctly describes the statue?
OA.
wooded
ОВ.
woody
OC.
non-wood
OD.
wooden
Answer:
Od- Wooden
Explanation:
It would not make sense if it was non-wood because that make it no a wood base product, OC is not right because its not a a plant that produces wood as its structural tissue and thus has a hard stem. An OA justT o take or get a supply of wood. so its Od
UV light has ______ wavelengths than visible light waves, and its peak energy is at a wavelength of ______.
Explanation:
Shorter wavelength since UV light has more energy than visible light
365 nm - What is the peak energy wavelength of UV light? It allows both infrared daylight and ultraviolet night-time communications by being transparent between 320 nm and 400 nm and also the longer infrared and just-barely-visible red wavelengths. Its maximum UV transmission is at 365 nm
When there is a temperature inversion, you would expect to experience Group of answer choices clouds with extensive vertical development above an inversion aloft. good visibility in the lower levels of the atmosphere and poor visibility above an inversion aloft. an increase in temperature as altitude increases.
Temperature inversion leads to an increase in temperature as altitude increases.
The term temperature inversion refers to a situation in which a layer of warm air lies over a layer of cool air. This is also referred to as thermal inversion. This occurs when the air below to loose heat rapidly.
One of the effects of temperature inversion is reduction in visibility. So, thermal inversion leads to an increase in temperature as altitude increases.
Learn more: https://brainly.com/question/8646601
The object in this diagram has a mass of 2 kg.
According to this diagram, what is the acceleration of this object?
A. 0 m/s2
B. 4 m/s2
C. 7 m/s2
D. 11 m/s2
Answer:
[tex]4 ms^{-2}[/tex]
Explanation:
Normal force - should be the reaction from the surface it's on - nullifies the weight of the object. At this point the only force is of [tex]22-14 = 8N[/tex] from whoever is pushing the square and the friction, towards the right. At this point we divide the force by the mass of the object to obtain an acceleration of [tex]8/2 = 4 ms^{-2}[/tex]
Kichelle enjoys balloon animals from the carnival. She just received a balloon giraffe that has an initial temperature of 39.0°C and a volume of 1.28 L. If Preston plays a trick on Kichelle, and puts her balloon giraffe into the freezer, what would be the new volume of the balloon if the temperature drops down to 8.0°C?
39°C=1.28L
8°C=? Less
=8°C/39°C×1.28L
=8/39×1.28L
=10.24/39
=512/195
=2.6L
Please help me calculate this question along with the equation
Hi there!
We can use the following:
U (Gravitational Potential Energy) = mgh
m = mass of object (kg)
g = acceleration due to gravity OR gravitational field strength
h = height, or displacement (m)
ΔU = Uf - Ui, so:
Uf = 3 × 1.5 × 10 = 45 J
Ui = 3 × 0 × 10 = 0
ΔU = Uf - Ui = 45 - 0 = 45 J
Choose all of the following that are compounds.
[]Air
[]Ink
[]Sodium (Na)
[]Mud
[]Hydrochloric acid (HCI)
[]Ocean water
[]carbon dioxide (CO2)
[]Hydrogen gas (H2)
[]water (H20)
Answer:
Ink
mud
hcl
ocean water
co2
h20
A ____ is a region where jets of gas from young stars impact and heat the gas surrounding the young star.
choose all the answers that apply.
Major areas of science include
____.
A.basic science
B.physical science
C.life science
D.social science
E. ethical science
Answer:
physical science
Explanation:
i guess??
The drone can fly for 25 minutes before the battery needs recharging. the power output of the battery is 65.0 watts. calculate the maximum energy stored by the battery
help please!! needed asap!!
Answer:
stored Energy = Power x time = 65 x 25x 60 = 105.6 Kjoules
please no irrelevant answers!
Light enters a glass block at an angle of incidence of 46°. The light refracts at an angle of refraction of 26°. What is the refractive index of the glass?
A 0.57
B 0.61
C 1.64
D 1.77
Answer:
Choice C: Approximately [tex]1.64[/tex].
(Assuming that light entered into this glass block from air.)
Explanation:
Let [tex]n_{1}[/tex] denote the refractive index of the first medium (in this example, air.) Let [tex]\theta_{1}[/tex] denote the angle of incidence.
Let [tex]n_{2}[/tex] denote the refractive index of the second medium (in this example, the glass block.) Let [tex]\theta_{2}[/tex] denote the angle of refraction.
By Snell's Law:
[tex]n_{1} \, \sin(\theta_{1}) = n_{2}\, \sin(\theta_{2})[/tex].
Rearrange the equation to find an expression for [tex]n_{2}[/tex], the refractive index of the second medium (the glass block.)
[tex]\begin{aligned}n_{2} = \left(\frac{\sin(\theta_{1})}{\sin(\theta_{2})}\right)\, n_{1}\end{aligned}[/tex].
The refractive index of air is approximately [tex]1.00[/tex]. Substitute in the values and solve for [tex]n_{2}[/tex], the refractive index of the glass block:
[tex]\begin{aligned}n_{2} &= \left(\frac{\sin(\theta_{1})}{\sin(\theta_{2})}\right)\, n_{1} \\ &= \left(\frac{\sin(46^{\circ})}{\sin(26^{\circ})}\right)\times 1.00 \\ &\approx 1.64\end{aligned}[/tex].
A 100 kg roller coaster comes over the first hill at 2 m/sec (vo). The height of the first hill (h) is 20 meters. See roller diagram below.
1) Find the total energy for the roller coaster at the initial point.
2) Find the potential energy at point A using the PE formula.
3) Use the conservation of energy to find the kinetic energy (KE) at point B.
4) Find the potential energy at point C.
5) Use the conservation of energy to find the Kinetic Energy (KE) of the roller coaster at point C.
6) Use the Kinetic Energy from C, find velocity of the roller coaster at point C.
For the 100 kg roller coaster that comes over the first hill of height 20 meters at 2 m/s, we have:
1) The total energy for the roller coaster at the initial point is 19820 J
2) The potential energy at point A is 19620 J
3) The kinetic energy at point B is 10010 J
4) The potential energy at point C is zero
5) The kinetic energy at point C is 19820 J
6) The velocity of the roller coaster at point C is 19.91 m/s
1) The total energy for the roller coaster at the initial point can be found as follows:
[tex] E_{t} = KE_{i} + PE_{i} [/tex]
Where:
KE: is the kinetic energy = (1/2)mv₀²
m: is the mass of the roller coaster = 100 kg
v₀: is the initial velocity = 2 m/s
PE: is the potential energy = mgh
g: is the acceleration due to gravity = 9.81 m/s²
h: is the height = 20 m
The total energy is:
[tex] E_{t} = KE_{i} + PE_{i} = \frac{1}{2}mv_{0}^{2} + mgh = \frac{1}{2}*100 kg*(2 m/s)^{2} + 100 kg*9.81 m/s^{2}*20 m = 19820 J [/tex]
Hence, the total energy for the roller coaster at the initial point is 19820 J.
2) The potential energy at point A is:
[tex] PE_{A} = mgh_{A} = 100 kg*9.81 m/s^{2}*20 m = 19620 J [/tex]
Then, the potential energy at point A is 19620 J.
3) The kinetic energy at point B is the following:
[tex] KE_{A} + PE_{A} = KE_{B} + PE_{B} [/tex]
[tex] KE_{B} = KE_{A} + PE_{A} - PE_{B} [/tex]
Since
[tex] KE_{A} + PE_{A} = KE_{i} + PE_{i} [/tex]
we have:
[tex] KE_{B} = KE_{i} + PE_{i} - PE_{B} = 19820 J - mgh_{B} = 19820 J - 100kg*9.81m/s^{2}*10 m = 10010 J [/tex]
Hence, the kinetic energy at point B is 10010 J.
4) The potential energy at point C is zero because h = 0 meters.
[tex] PE_{C} = mgh = 100 kg*9.81 m/s^{2}*0 m = 0 J [/tex]
5) The kinetic energy of the roller coaster at point C is:
[tex] KE_{i} + PE_{i} = KE_{C} + PE_{C} [/tex]
[tex] KE_{C} = KE_{i} + PE_{i} = 19820 J [/tex]
Therefore, the kinetic energy at point C is 19820 J.
6) The velocity of the roller coaster at point C is given by:
[tex] KE_{C} = \frac{1}{2}mv_{C}^{2} [/tex]
[tex] v_{C} = \sqrt{\frac{2KE_{C}}{m}} = \sqrt{\frac{2*19820 J}{100 kg}} = 19.91 m/s [/tex]
Hence, the velocity of the roller coaster at point C is 19.91 m/s.
Read more here:
https://brainly.com/question/21288807?referrer=searchResults
I hope it helps you!