Answer:
v = 12.1 m/s
Explanation:
When at the top of the circle, there are two forces acting on the combined mass of the rider and the motorcycle.These are the force of gravity (downward) and the normal force, which is directed from the surface away from it, perpendicular to the surface.In this case, as the motorcycle runs in the interior of the circle, at the top point this force is completely vertical, and is also downward.Since the motorcycle is moving in a vertical circle, there must be a force, keeping the object moving around a circle.This force is the centripetal force, aims towards the center of the circle, and is just the net force aiming in this direction at any point.At the top point, this force is just the sum of the normal force and the weight of the mass of the rider and the motorcycle combined, as follows (we take the direction towards the center as positive):[tex]F_{c} = N + m*g (1)[/tex]
Now, we know that the centripetal force is related with the tangential speed at this point and the radius of the circle as follows:[tex]F_{c} = m*\frac{v^{2}}{r} (2)[/tex]
Since the normal force takes any value as needed to make (1) equal to (2), if the speed diminishes, it will be needed less force to keep the equality valid.In the limit, when the motorcyvle tires barely touch the surface, this normal force becomes zero.In this condition, from (1) and (2), we can find the minimum possible value of the speed that still keeps the motorcycle touching the surface, as follows:[tex]v_{min} =\sqrt{r*g} =\sqrt{15.0m*9.8m/s2} = 12.1 m/s (3)[/tex]If the net force acting on an object is 0 N, you can be sure that the forces acting on the object are
A. balanced B.Unbalanced C. acting at the same direction
I think the answer would be A.
After all, it is 0 which is technically a dead center number meaning that the net should be balanced and still.
Hope this helps and have a nice day.
-R3TR0 Z3R0
The Hall effect can be used to determine the density of mobile electrons in a conductor. A thin strip of the material being investigated is immersed in a magnetic field and oriented so that its surface is perpendicular to the field. In a particular measurement, the magnetic field strength was 0.685 T, the strip was 0.107 mm thick, the current along the strip was 2.25 A, and the Hall voltage between the strip's edges was 2.59 mV.Find the density nof mobile electrons in the material. The elementary charge is 1.602×10−19 C.
Answer:
the density of mobile electrons in the material is 3.4716 × 10²⁵ m⁻³
Explanation:
Given the data in the question;
we make use of the following expression;
hall Voltage VH = IB / ned
where I = 2.25 A
B = 0.685 T
d = 0.107 mm = 0.107 × 10⁻³ m
e = 1.602×10⁻¹⁹ C
VH = 2.59 mV = 2.59 × 10⁻³ volt
n is the electron density
so from the form; VH = IB / ned
VHned = IB
n = IB / VHed
so we substitute
n = (2.25 × 0.685) / ( 2.59 × 10⁻³ × 1.602×10⁻¹⁹ × 0.107 × 10⁻³ )
n = 1.54125 / 4.4396226 × 10⁻²⁶
n = 3.4716 × 10²⁵ m⁻³
Therefore, the density of mobile electrons in the material is 3.4716 × 10²⁵ m⁻³
Four bicyclists travel different distances and times along a straight path. Which cyclist traveled with the greatest average
speed?
A
B
Cyclist 2 travels
87 min 22 s
Cyclist 4 travels
108 min 24 s
D
Cyclist 1 travels
95 m in 27 s
Cyclist 3 travels
106 m in 26 s
Answer:
The cyclist with the greatest average speed is Cyclist 4 with average speed of 4.5 m/s
Explanation:
Given;
Cyclist 1 travels 9 m in 27 s
Cyclist 2 travels 87 m in 22 s
Cyclist 3 travels 106 m in 26 s
Cyclist 4 travels 108 m in 24 s
Determine the average speed of the cyclists as follows;
Average speed of Cyclist 1: v = 9/27 = 0.33 m/s
Average speed of Cyclist 2: v = 87/22 = 3.96 m/s
Average speed of Cyclist 3: v = 106/26 = 4.08 m/s
Average speed of Cyclist 4: v = 108/24 = 4.5 m/s
Therefore, the cyclist with the greatest average speed is Cyclist 4 with average speed of 4.5 m/s
1. An object with a mass of 5 kg is pushed by a force of 10 N. What is the object's acceleration?
Answer:2m/s^2
Explanation:
a=f/m
A trapeze artist swings in simple harmonic motion with a period of 3.8 s.
Calculate the length of the cables supporting the trapeze. (g=9.81 m/s2)
A Sonometer wire of length
l vibrates at a
frequency of
350 Hz. when the length of the
wire is increased by 15cm, the
Wire Vibrates at 280 H₂ under
constant tension. Determine l
Answer:
-75 cm
Explanation:
At l ; F = 350 Hz
At l + 15 cm ; F = 280 Hz
I = 350
I + 15 = 280
280I = 350(I + 15)
280I = 350I + 5250
280I - 350I = 5250
-70I = 5250
I = - 75cm
The length is - 75 cm
An elevator suspended by a vertical cable is moving downward at a constant speed. The tension in the cable must be A) greater than the weight of the elevator. B) less than the weight of the elevator. C) equal to the weight of the elevator.
Answer:
(C) because the elevator is not accelerating
Note F = M a = M g (the resultant force on the elevator is due to gravity)
or Fup = Fc the force exerted on the elevator by the cable
and Fdown = Fe the force exerted on the elevator by gravity
F = M a = Fup - Fdown = zero resultant force on elevator
What do Ice core samples with lower ratios of O-18 to O-16 isotopes tell scientist about past climates
Answer:
Ocean-floor sediments can also be used to determine past climate. ... Ice cores contain more 16O than ocean water, so ice cores have a lower 18O/ 16O ratio than ocean water or ocean-floor sediments. Water containing the lighter isotope 16O evaporates more readily than 18O in the warmer subtropical regions
Explanation:
Which type of biological molecule would control cell activities?
A) Amino Acids.
C) Nucleic Acids.
B) Lipids.
D) Carbohydrates.
Answer:
C. Nucleic Acids.
Explanation:
Nucleic acids are thus uniquely capable of directing their own self-replication, allowing them to function as the fundamental informational molecules of the cell. The information carried by DNA and RNA directs the synthesis of specific proteins, which control most cellular activities.
Did some simple research, if that's fine and I hope this is correct as it says on the sites. Have a good one :)
In 2014, physicists from FOM Foundation at the University of Amsterdam introduced a new hypothesis of how the Pyramids at Giza were built. The group of physicists suggestedthat ancient Egyptians wetted sand in an effort toreduce friction and then pulled the 3000 kg stoneblocks to their final resting place. 15 men couldmove a block at a rate of 0.5m/sby pulling a largerope angled at 30owith respect to the plane anda tension of 7,200 N.
Required:
a. What is net work done on block?
b. What is speed of blck after it moved .25m?
c. What is work done by block if kinetic friction coefficient is 0.3?
d. What is net work including friction?
Answer:
The correct answer is:
(a) 0
(b) 0.5 m/s
(c) 7740 N
(d) 0
Explanation:
The given values are:
mass,
m = 3000 kg
Tension,
T = 7,200 N
Angle,
= 30°
(a)
Even as the block speed becomes unchanged, the kinetic energy (KE) will adjust as well:
⇒ [tex]\Delta K =0[/tex]
By using the theorem of energy, the net work done will be:
⇒ [tex]\Delta K =0[/tex]
(b)
According to the question, After 0.25 m the block is moving with the constant speed
= 0.5 m/s.
(c)
The given kinetic friction coefficient is:
u = 0.3
The friction force will be:
= [tex]u(mg-Tsin30^{\circ})[/tex]
On substituting the values, we get,
= [tex]0.3[(3000\times 9.8)-(7200\times 0.5)][/tex]
= [tex]0.3[29400-3600][/tex]
= [tex]0.3\times 25800[/tex]
= [tex]7,740 \ N[/tex]
(d)
On including the friction,
The net work will be:
⇒ [tex]\Delta K=0[/tex]
Classes are canceled due to snow, so you take advantage of the extra time to conduct some physics experiments. You fasten a large toy rocket to the back of a sled and take the modified sled to a large, flat, snowy field. You ignite the rocket and observe that the sled accelerates from rest in the forward direction at a rate of 11.5 m/s^2 for a time period of 3.30 s. After this time period, the rocket engine abruptly shuts off, and the sled subsequently undergoes a constant backward acceleration due to friction of 4.15 m/s^2.
Required:
a. After the rocket turns off, how much time does it take for the sled to come to a stop?
b. By the time the sled finally comes to a rest, how far has it traveled from its starting point?
Answer:
a) t = 9.2s
b) Δx = 242.2 m
Explanation:
a)
In order to find the time that the sled traveled since the rocket was turned off, we need to find the first the speed that it had at that moment.Applying the definition of accceleration, since we know that the sled started from rest, we can find the value of the final speed (for this part) as follows:[tex]v_{f1} = a_{1} * t_{1} = 11.5m/s2* 3.30 s = 38.0 m/s (1)[/tex]
This speed, is just the initial speed for the second part, so we can find the time traveled from the moment the rocket was turned off until it came to an stop, as follows:[tex]t_{2} = \frac{v_{f1}}{a_{2} } = \frac{38m/s}{4.15m/s} = 9.2 s (2)[/tex]
b)
We need to find find first the displacement when the sled was accelerating.Assuming the acceleration is constant, since it started from rest, we can use the following kinematic equation:[tex]v_{f1} ^{2} = 2* a_{1} * x_{1} (3)[/tex]
Solving for x₁:[tex]x_{1} =\frac{v_{f1}^{2} }{2*a_{1}} =\frac{(38m/s)^{2} }{2*11.5m/s2} =62.8 m (4)[/tex]
In the same way, we can use the same equation, replacing the values of the final speed (which becomes zero), initial speed (which is the same as vf1), and a, which becomes -4.15 m/s2 as it is backwards.[tex]-v_{f1} ^{2} = 2* a_{2} * x_{2} (5)[/tex]
Solving for x₂:[tex]x_{2} =\frac{-v_{f1}^{2} }{2*a_{2}} =\frac{-(38m/s)^{2} }{2*(-4.15m/s)^2} =174.0 m (6)[/tex]
Δx = x₁ + x₂ = 68.2 m + 174.0 m = 242.2 m (7)An object swings in a horizontal circle, supported by a 1.8-m string. It swings at a speed of 3 m/s. What is the mass of the object given that the tension in the string is 90 N?
Answer:
Mass = 18 kg
Explanation:
Formula for force in centripetal motion is;
F = mv²/r
We have;
Mass; m.
Speed; v = 3 m/s
radius; r = 1.8 m
Force; F = 90 N
Thus;
Making m the subject;
m = Fr/v²
m = 90 × 1.8/3²
m = 18 kg
5) In the last part of step 7 of the procedure, you measured the resistance of the flashlight when it had no current passing through it. The resistance of the flashlight is different, however, when current is passing through it. Explain how your measurement of the resistance of the variable resistor obtained in part 7 is a valid approximation of the resistance of the flashlight when it had current passing through it. Is the resistance higher when the flashlight is on or off
Answer:
Following are the responses to this question:
Explanation:
The small current passes thru the capacitor of the strain gauge and the current is generated throughout the resistor. For the very first time, in contrast to what we calculate, its resistance of the multimeter is quite high and therefore the small stream flowing through the bulb would have very little impact on the measure. Thus, as the current flows through the flashbulb, this same calculation is of excellent price, its material is heated and resistance varies with increase. Therefore, when the bulb will be on, sensitivity is greater.
The slope of a displacement time graph for a uniform motion represent what
Answer:
Velocity.
Explanation:
The slope of a displacement time graph for a uniform motion represent the gradient of the line i.e. the velocity of the object.
The velocity of an object is given by :
v = d/t
Where
d is displacement
t is time
Hence, the slope of the displacement-time graph gives the velocity of the object.
What happens to solar radiation when it is absorbed
Answer:
Absorbed sunlight is balanced by heat radiated from Earth's surface and atmosphere. ... The atmosphere radiates heat equivalent to 59 percent of incoming sunlight; the surface radiates only 12 percent. In other words, most solar heating happens at the surface, while most radiative cooling happens in the atmosphere
For the circuit in the previous part, the current flowing in the wire between the positive terminal of the battery and the resistor is ___________ the current flowing between the resistor and the negative terminal of the battery. For the circuit in the previous part, the current flowing in the wire between the positive terminal of the battery and the resistor is ___________ the current flowing between the resistor and the negative terminal of the battery. less than equal to greater than
Answer:
Explanation:
because it is godhood
When an
object is placed 15 cm from "
a concave mirror, a real image magnified
3 times is formed - Find
a) the focal length of the mirror
b) where the object must be placed to
give a virtual image 3 times the height
of the object
Answer:
Focal length(f)= -15 cm, magnification= -3 (image is real). So, -v/u=-3 ; or v=3u {v=image distance and u=object distance}. Using mirror formula,
1/f= 1/v + 1/u
-1/15 = 1/3u + 1/u
4/3u = -1/15
u= -20 cm
v =3u= 3×(-20)= -60 cm
So object is 20 cm and image is 60 cm in front of the mirror.
Explanation:
A student picks up two spheres that are the same size. One is made of steel and the other is made of aluminum. The student notices that the steel sphere feels much heavier than the aluminum sphere. He then holds one sphere in each hand at eye level and lets go of them at the same time. They fall to the floor. Which ball, if any, will hit the ground first and for what reason
Answer:
They will fall at the same time. This is because gravity accelerates all objects at the same speed, Earth's gravity being approximately 9.8m/s²
They'll both fall at the same time. This is because gravity accelerates everything at the same rate, with Earth's gravity being approximately 9.8 m/s2.
What is gravity with some instances?The energy that holds the gases inside the sun together. the force that causes a ball to fall after being thrown into the air the force that causes a car to coast downhill even when the gas pedal is not depressed the force that causes a glass to shatterGravity, also known as gravitation, affects all material objects in the universe. Gravity attracts any two objects or particles with nonzero mass toward one another. Gravity affects everything from subatomic particles to galaxy clusters. Gravity is the attraction force between two objects. It's what causes things to fall and keeps us from floating away into space. Gravity is a fundamental natural force.To learn more about gravity, refer to:
https://brainly.com/question/16275567
#SPJ2
Are we within earths Roche limit
Answer: Closer to the Roche limit, the body is deformed by tidal forces. Within the Roche limit, the mass' own gravity can no longer withstand the tidal forces, and the body disintegrates. hope this helps can u give me brainliest
Explanation:
What is heredity and how does it influence physical fitness?
6. A garden hose attached to a nozzle is used to fill a 15-gal bucket. The inner diameter of the hose is 1.5 cm, and it reduces to 0.8 cm at the nozzle exit. If it takes 50 s to fill the bucket with water (density = 1 kg/L), determine (a) the volume and mass flow rates of water through the hose, and (b) the average velocity of water at the nozzle exit.
Answer: 1.135 L/s; 1.35 kg/s, 22.57 m/s
Explanation:
Given
Volume of bucket [tex]V=15\ gal\approx 56.78\ L[/tex]
time to fill it [tex]t=50\ s[/tex]
Volume flow rate
[tex]\dot{V}=\dfrac{56.78}{50}=1.135\ L/s\approx 1.135\times 10^{-3}\ m^3/s[/tex]
The inner diameter of the hose [tex]D=1.5\ cm[/tex]
diameter of the nozzle exit [tex]d=0.8\ cm[/tex]
we can volume flow rate as
[tex]\Rightarrow \dot{V}=Av\quad \quad \text{v=average velocity through nozzle exit}\\\\\Rightarrow 1.135\times 10^{-3}=\frac{\pi }{4}d^2\times v\\\\\Rightarrow 1.135\times 10^{-3}=\frac{\pi }{4}(0.8\times 10^{-2})^2\times v\\\\\Rightarrow v=\dfrac{4\times 1.135\times 10^{-3}}{\pi \times 64\times 10^{-6}}=22.57\ m/s[/tex]
Mass flow rate
[tex]\Rightarrow \dot{m}=\rho \times \dot{V}\\\Rightarrow \dot{m}=1\ kg/L\times 1.135\ L/s=1.35\ kg/s[/tex]
In the legend of William Tell, Tell is forced to shoot an apple from his son's head for failing to show respect to a high official. In our case, let's say Tell stands 8.7 meters from his son while shooting. The speed of the 144-g arrow just before it strikes the apple is 20.4 m/s, and at the time of impact it is traveling horizontally. If the arrow sticks in the apple and the arrow/apple combination strikes the ground 8 m behind the son's feet, how massive was the apple
Answer:
M = 0.31 kg
Explanation:
This exercise must be done in parts, let's start by finding the speed of the set arrow plus apple, for this we define a system formed by the arrow and the apple, therefore the forces during the collision are internal and the moment is conserved
let's use m for the mass of the arrow with velocity v₁ = 20.4 m / s and M for the mass of the apple
initial instant. Just before the crash
p₀ = m v₁ + M 0
instant fianl. Right after the crash
p_f = (m + M) v
p₀ = p_f
m v₁ = (m + M) v
v =[tex]\frac{m}{m+M} \ v_1[/tex] (1)
now we can work the arrow plus apple set when it leaves the child's head with horizontal speed and reaches the floor at x = 8 m. We can use kinematics to find the velocity of the set
x = v t
y = y₀ + [tex]v_{oy}[/tex] t - ½ g t²
when it reaches the ground, its height is y = 0 and as it comes out horizontally, [tex]v_{oy} = 0[/tex]
0 = h - ½ g t²
t² = 2h / g
For the solution of the exercise, the height of the child must be known, suppose that h = 1 m
t = [tex]\sqrt{ \frac{ 2 \ 1}{9.8} }[/tex]
t = 0.452 s
let's find the initial velocity
v = v / t
v = 8 / 0.452
v = 17.7 m / s
From equation 1
v = m / (m + M) v₁
m + M = [tex]m \ \frac{v_1}{v}[/tex]
M = m + m \ \frac{v_1}{v}
we calculate
M = 0.144 + 0.144 [tex]\frac{20.4}{17.7}[/tex]
M = 0.31 kg
6. As distance increases, gravitational force *
(10 Points)
increases
decreases
A 45.0 kilogram boy is riding a 15.0-kilogram bicycle with a speed of 8.00 meters per second. What is the combined kinetic energy of the boy and the bicycle? A)480.J B)240.0J C)1920J D)1440J
Answer:
1920Joules
Explanation:
The formula for calculating the kinetic energy of a body is expressed as;
KE = 1/2 mv²
m isthe mass
V is the speed
For the two masses, the combined KE is expressed as;
KE = 1/2(m1+m2)v²
KE = 1/2(45+15)(8)²
KE = 1/2 * 60 * 64
KE = 30 * 64
KE = 1920J
Hence the combined kinetic energy of the boy and the bicycle is 1920Joules
The combined kinetic energy of the boy and the bicycle is of 1920 J.
Given data:
The mass of boy is, m = 45.0 kg.
The mass of bicycle is, M = 15.0 kg.
The speed of bicycle is, v = 8.00 m/s.
The kinetic energy of an object is defined as the energy possessed by an object by virtue of motion of object. The combined kinetic energy of the boy-bicycle system is given as,
[tex]KE = \dfrac{1}{2}(m+M)v^{2}[/tex]
Solve by substituting the values as,
[tex]KE = \dfrac{1}{2}(45+15) \times 8^{2}\\\\KE = 1920 \;\rm J[/tex]
Thus, we can conclude that the combined kinetic energy of the boy and the bicycle is of 1920 J.
Learn more about the concept of kinetic energy here:
https://brainly.com/question/12669551
HELP DUE 3 MINUTESSSSD
Answer:
Break down small pebbles and sediments, like sand
Break down large rocks like mountains
Explanation:
If the object on the Moon were raised to a height of 30.0 m, what would be the potential energy? PE=mgh (g on the Moon is 1.62m/s)
Which of these would have the highest temperature?
ice
· Water
water vapor
Answer:
water vapor
Explanation:
did assignment on edge
A frictionless pendulum is made with a bob of mass 12.6 kg. The bob is held at height = 0.650 meter above the bottom of its trajectory, and then pushed
forward with an initial speed of 4.22 m/s. What amount of mechanical energy does the bob have when it reaches the bottom?
A load of mass 120kg is raised
vertically through a height of 2m in
30s by a machine whose efficiency,
is 100% Calculate the power generated
by the machine
Answer: P = 120 kg·9.81 m/s² · 2 m / 30 s = 78 W
Explanation: power P = Work done / time
Work is lifting work = mgh in which g = 9.81 m/s²
Time 30 s
can someone please help me I am so behind I neee to catch up but I need it to be correct both of them
Answer:
1.B, 2.A
Explanation: