Answer:
Explanation:
1/v - 1/u = 1/f
given, f = 0.3 m, u = -0.4m
so, 1/v - 1/-0.4 = 1/0.3
or, 1/v = 1/0.3 - 1/0.4 = 1/1.2
v = 1.2 m
now, differentiating 1/v - 1/u = 1/f with respect to t,
-1/v² dv/dt + 1/u² du/dt = 0
or, dv/dt = (v/u)² du/dt
putting, du/dt = 0.01 m/s , v = 1.2 m and u = -0.4 m
so, dv/dt = (1.2/-0.4)² × 0.01
= 0.09 m/s
hence, speed of image with respect to lens is 0.09 m/s .
from formula of magnification
magnification, m = v/u
differentiating with respect to time both sides,
dm/dt = (u dv/dt - vdu/dt)/u²
= (-0.4 × 0.09 - 1.2 × 0.01)/(-0.4)²
= (-0.036 - 0.012)/0.16
= -0.048/0.16
= -0.3 m/s
hence, magnitude of rate of change of lateral magnification is 0.3 m/s
which of the following changes will increase the frequency of an oscillating pendulum?
a. an increase in the mass of the pendulum.
b. an increase in the initial height of release.
c. an increase in the length of the rope.
d. more than one of the above
e. none of the above
explain your answer in your own words.
NO LINKS.
Answer:
b (i think)
Explanation:
write the formula of mechanical advantage
Answer:
the formula of mechanical advantage is
MA = load / effort
VR = effort distance / load distance
hope it is helpful to you
You throw a ball straight up. Compare the sign of the work done by gravity while the ball goes up with the sign of the work done by gravity while it goes down.
a. Work is + on the way up and + on the way down
b. Work is + on the way up and - on the way down
c. Work is - on the way up and + on the way down
d. Work is - on the way up and - on the way down
Answer:
c. Work is - on the way up and + on the way down
Explanation:
Work done is given as the product of the applied force and the displacement of the object.
Work done = F x d
Work done = mg x d
where;
g is acceleration due to gravity = 9.8 m/s²
When the ball goes up, it moves against the force of gravity which tends to pull every object downwards. Since the ball moves against gravity, the work done is negative.
Also, when the ball goes down, it moves in the direction of gravity which acts downwards. Since the ball moves in the same direction as gravity, the work done is positive.
The correct option is "C. Work is negative (-) on the way up and positive (+) on the way down"
URGENT!!!!!!!!!: If an electromagnetic wave has a frequency of 6 x 10^5 Hz, what is its
wavelength? Use v/f. The speed of light is 3 x 10^8 m/s.
Answer:
A
Explanation:
because the speed divide by the frequency is equal to the wavelength(in meters)
5×10² m
Future space stations could create an artificial gravity by rotating. Consider a cylindrical space station that rotates with a period of 28 seconds about its axis. Astronauts walk on the inside surface of the space station, and they experience an Earth-like gravitational acceleration of 9.8 m/s2. What is the diameter of the space station?
510m
145m
660m
390m
Answer:
P = 2 pi R / v period of space station
F / m = v^2 / R centripetal force per unit of mass
So F / m = 4 pi^2 R^2 / (P^2 * R) = 4 pi^2 R / P^2
Also, F / m = 9.8 m/s^2 earth's gravitational attraction
So 9.8 = 4 pi^2 R / P^2 or R = 9.8 P^2 / 4 * pi^2) = 195 m
Or D = 2 R = 390 m the diameter required
PLS HELPP MEEE
Fiber-optic cables rely on total internal reflection.
Please select the best answer from the choices provided
T
F
Question 6 of 10
The mass number of a nucleus decreases during which nuclear reactions?
A. Nuclear fusion and alpha decay
B. Nuclear fission and beta decay (electron emission)
C. Nuclear fusion and beta decay (positron emission)
D. Nuclear fission and alpha decay
Answer:
D. Nuclear Fission and alpha decay
Typical novae occur when (a) a red-giant star ejects a planetary nebula; (b) two neutron stars merge, forming a more massive neutron star; (c) an extremely massive star collapses, and also ejects its outer atmosphere; (d) matter accreted from a companion star unstably ignites on the surface of a white dwarf; or (e) a neutron star’s magnetic field becomes strong enough to produce two oppositely directed jets of rapidly moving particles.
Answer:
I think its d matter accreted from a companion star unstable ignites on the surface of a white dwarf.
What does the potential energy diagram of a chemical reaction tell you?
O A. Whether atoms are being created or destroyed
O B. Whether the reaction is endothermic or exothermic
C. Whether there are more reactants or products
D. Whether the law of conservation of matter is being obeyed
Answer:
B
Explanation:
I'm learning about this now actually and it can be a little confusing but it would be endothermic or exothermic. if endothermic the products have less energy than the reactants and if exothermic products have more energy than reactants
23. Lunar Gravity Compare the force holding a
10.0-kg rock on Earth and on the Moon. The
gravitational field on the Moon is 1.6 N/kg.
Explanation:
Given
mass of the rock is 10 kg
Force requires to hold the rock is equal to its weight
Weight is given by the product of mass and acceleration due to gravity
Weight on the earth surface
[tex]\Rightarrow W_e=10\times 9.8\\\Rightarrow W_e=98\ N[/tex]
Weight on the moon surface
[tex]\Rightarrow W_m=1.6\times 10\\\Rightarrow W_m=16\ N[/tex]
So, the force holding the rock on earth is approximately 6 times the force on the moon.
A 1800-kg Jeep travels along a straight 500-m portion of highway (from A to B) at a constant speed of 10 m/s. At B, the Jeep encounters an unbanked curve of radius 50 m. The Jeep follows the road from B to C traveling at a constant speed of 10 m/s while the direction of the Jeep changes from east to south. What is the magnitude of the acceleration of the Jeep as it travels from A to B
Answer:
a = 0 m/s²
Explanation:
From A to B the jeep travels in a straight line with a constant speed of 10 m/s. Acceleration is defined as the rate of change in velocity. In the current scenario, the velocity of the jeep remains constant. The direction of the jeep does not change as it travels in the straight path. Also, the magnitude of the velocity is constant at 10 m/s.
Therefore, there is no change in the velocity of the jeep from A to B. Hence, the will be no acceleration from A to B.
a = 0 m/s²
Any is 160 cm tall and stands 50 cm in front of a plane mirror. The image of Amy is ?
Answer:
Option A. 160 cm tall and 100 cm in front of Amy
Explanation:
To know the the correct answer to the question, we must recognise that the image formed by plane mirror is:
I. Same size as the object.
II. Same distance as the object from the mirror.
III. Laterally inverted.
IV. Virtual
With the above information, we obtained the answer to the question as follow:
Object height = 160 m
Thus,
Image height = 160 m
Distance of object from mirror = 50 cm
Therefore,
Distance of image from the mirror = 50 cm
Distance between the object and image = 50 + 50 = 100 cm
Thus, option A gives the correct answer to the question because the image of Amy is 160 cm tall and 100 cm in front of her.
What are 3 facts you learned about the periodic table:
Answer: the rarest element is Francium. J is not on the periodic table. also Dmitri Mendeleev proposed the periodic table.
Explanation: Kinda looked the last one up.
Descriptions of the sky at various locations on Earth
Which quantity does not change when there is an increase in temperature?
Answer:
But Mass of solids does not depend upon the temperature because it is matter contained in the solids.
Explanation:
The mass is the quantity which does not change when there is an increase in temperature.
What is mass?A tangible body's mass is the amount of matter it possesses. It's also a metric of inertial, or the resistance to velocity when a net force is exerted.
The quantity does not change when there is an increase in temperature is mass because it is matter that makes up solids, their mass is unaffected by temperature.
Thus, the mass is the quantity which does not change when there is an increase in temperature.
Learn more about the mass here:
https://brainly.com/question/15959704
#SPJ2
Water in an electric teakettle is boiling. The power absorbed by the water is 0.90 kW. Assuming that the pressure of vapor in the
kettle equals atmospheric pressure, determine the speed of effusion of vapor from the kettle's spout if the spout has a cross-
sectional area of 1.60 cm2. Model the steam as an ideal gas.
Answer:
v = 4.233 m/s
Explanation:
By applying the rate of boiling from [tex]Q= mL_v[/tex];
the rate of the boiling can be described as:
[tex]\mathcal{P} = \dfrac{Q}{\Delta t} \\ \\ \mathcal{P} = \dfrac{mL_v}{\Delta t}[/tex]
The mode of the steam (water vapor) as an ideal gas can be illustrated by formula:
[tex]P_oV_o = nRT[/tex] --- (1)
where;
n = number of moles;
[tex]n = \dfrac{mass (m)}{Molar mass (M)}[/tex]
Then; equation (1) can be rewritten as:
[tex]P_oV_o = (\dfrac{m}{M}) RT \\ \\ \dfrac{P_oV}{\Delta T} = \dfrac{m}{\Delta t} ( \dfrac{RT}{M})[/tex]
∴
[tex]\dfrac{m}{\Delta t} = \dfrac{\mathcal{P}}{L_v}[/tex]
Then:
[tex]P_o \times A \times v= \dfrac{\mathcal{P}}{L_v}\Big ( \dfrac{RT}{M }\Big)[/tex]
making (v) the subject of the formula:
[tex]v= \Big ( \dfrac{\mathcal{P} RT}{M\times L_v \times P_o \times A }\Big)[/tex]
Given that:
[tex]\mathcal{P}[/tex] = 0.90 kW = 900 W
R(rate constant) = 8.314 J/mol.K
Temperature at 100° C = 373K
For water vapor:molar mass= 18.015 g/mol ≅ 0.0180 kg/mol
Latent heat of vaporisation [tex]L_v[/tex] = 2.26 × 10⁶ J/kg
Atmospheric pressure [tex]P_o = 1.013 \times 10^6 \ N/m^2[/tex]
Cross sectional area A =1.60 cm² = 1.60 × 10⁻⁴ m²
[tex]v= \Big ( \dfrac{900 W (8.314 \ J/mol.K)(373)}{0.0180 \ kg/mol) (2.26 \times 10^6 \ J/kg) (1.013 \times 10^5 \ N/m^2)(1.60 \times 10^{-4} \ m^2)}\Big)[/tex]
v = 4.233 m/s
Convert 0.00553s to cs
Answer: 0.553
Explanation:
what is acceleration?
Answer:
the rate of change of velocity per unit of time.
Answer:
accelerate is rate of chang of velocity
A piece of stone of mass 80 g is
dropped into a measuring cylinder
containing water. The water level
increases from 12 cm² to 37 cm
Calculate the density of the stone.
A. 32 g/cm
B. 3.2 g/cm
C. 320 g/cm
D. 3.20 g/cm
8
37+12
Answer:
this is how I know it though my answer is not in the choices
Explanation:
M=80g
V=37cm-12 cm
15cm
Density=mass/volume
80g/15cm3
5.33g/cm3
PLEASE HELP ME WITH THOSE TWO QUESTIONS
A 122 Ohm, 232 Ohm, and 500 Ohm resistors are all connected in series with a 12 V battery. What is the current flowing through them?
A 100 Ohm, 200 Ohm, and 300 Ohm resistor are all connected in series to a 12 V battery. What is the potential difference drop across the 100 Ohm resistor?
Answer:
(a) 0.014 A
(b) 2 V
Explanation:
(a) Applying
V = IR'...................... Equation 1
Where V = Voltge, I = current, R = total resistance.
make I the subject of the equation
I = V/R'................... Equation 2
From the question,
Given: V = 12 V, R' = (122+232+500) ohms (The resistance are connected in series) = 854 ohms
Substitute these values into equation 2
I = 12/854
I = 0.014 A
(b) Applying
V' = V(R₁)/(R₁+R₂+R₃)...................... Equation 3
Where V' = Voltage across the 100 ohms resistor.
From the question,
V = 12V, R₁ = 100 ohm, R₂ = 200 ohm, R₃ = 300 ohm.
Substitute these values into equation 3
V' = (12×100)/(100+200+300)
V' = 1200/600
V' = 2 V
A 1.5 V battery is connected to a 1,000 μF capacitor in series with a 150 Ω resistor. a. What is the maximum current that flows through the resistor during charging? b. What is the maximum charge on the capacitor? c. How long does the capacitor take to reach a potential of 1.0V?
Answer:
[tex]0.01\ \text{A}[/tex]
[tex]0.0015\ \text{C}[/tex]
[tex]0.0608\ \text{s}[/tex]
Explanation:
[tex]V_0[/tex] = Voltage = 1.5 V
[tex]C[/tex] = Capacitance = [tex]1000\ \mu\text{F}[/tex]
[tex]R[/tex] = Resistance = [tex]150\ \Omega[/tex]
Current is given by
[tex]I=\dfrac{V_0}{R}\\\Rightarrow I=\dfrac{1.5}{150}\\\Rightarrow I=0.01\ \text{A}[/tex]
Current flowing in the resistor is [tex]0.01\ \text{A}[/tex].
Charge is given by
[tex]Q=CV\\\Rightarrow Q=1000\times 10^{-6}\times 1.5\\\Rightarrow Q=0.0015\ \text{C}[/tex]
The charge on the capacitor is [tex]0.0015\ \text{C}[/tex].
Voltage is given by
[tex]V=V_0e^{-\dfrac{t}{RC}}\\\Rightarrow t=-RC\ln\dfrac{V}{V_0}\\\Rightarrow t=-150\times 1000\times 10^{-6}\times\ln\dfrac{1}{1.5}\\\Rightarrow t=0.0608\ \text{s}[/tex]
Time taken to reach 1 V is [tex]0.0608\ \text{s}[/tex].
If a body of mass 2 kg is moving with a velocity of 30 m/s, then on doubling its velocity the momentum becomes______.
a-60kgm/s
b-120kgm/s
c-90kgm/s
D-30kgm/s
An ant is crawling along a straight wire, which we shall call the x axis, from A to B to C to D (which overlaps A), as shown in the figure below. O is the origin. Suppose you take measurements and find that AB is 31 cm , BC is 12 cm , and AO is 7 cm .(Figure 1)
A. What is the ant’s position at point A?
B. What is the ant’s position at point B?
C. What is the ant’s position at point C?
D. What is the ant’s position at point D?
Answer:
Ants position at point A = -7 cm
Ants position at point B = 38 cm
Ants position at point C = 26 cm
Ants position at point D = -7 cm
Explanation:
In this question, we are dealing with displacement which is the change in position of an object.
Now, we are told the journey began from A to B and then from C to D.
Now, AB = 31 cm and AO = 7cm
But along AB, we have the origin O.
Since A is on the left hand side of the origin, it means it is negative. Thus, position A = -7cm
Then position B = 31 - (-7) = 31 + 7 = 38 cm
Since BC = 12cm, then position C = 38 - 12 = 26 cm
Position D is same as position A = -7cm
Two people are carrying a uniform 704.0 N log through the forest. Bubba is 2.2 m from one end of the log (x), and his partner is 0.9 m from the other end (y). The log is 6.2 m long (z). What weight is Bubba supporting
Answer:
F₁ = 499.61 N , this is the force that Bubba support
Explanation:
The trunk is in equilibrium with the two forces applied by man, let's use the equilibrium relation
let's set a reference frame at the extreme left and assume that the counterclockwise rotations are positive
Let's write the expression for the translational equilibrium
subscript 1 is for Bubba's mass and subscript 2 for his partner
F₁ + F₂ -W = 0
F₁ + F₂ = W
the expression for rotational equilibrium
∑ τ = 0
F₁ 2.2 + F₂ (6.2-0.9) - W 6.2/2 = 0
2.2 F1 + 5.3 F2 = 3.1 W
let's write our system of equations
F₁ + F₂ = W
2.2 F₁ + 5.3 F₂ = 3.1 W
we solve for F₁ in the first equation and substitute in the second
F₁ = W-F₂
2.2 (W- F₂) + 5.3 F₂ = 3.1 W
F₂ ( -2.2 +5.3) = W (3.1 - 2.2)
F₂ = 704 0.9 / 3.1
F₂ = 204.39 N
This is the force that the partner supports
we look for F1
F₁ = W-F₂
F₁ = 704 - 204.39
F₁ = 499.61 N
This is the force that Bubba support
In the diagram shown below, the distance from the dotted line to Point A, or the distance from the dotted line to Point D is known as the
Answer:
The dotted line connecting two points is known as the distance traveled.
Explanation:
The distance traveled is a physical quantity that refers to the total displacement of a body. This distance is usually shown as a dotted line that connects two points in an image. In general, we can say that the distance traveled is calculated by adding all the distances that an element makes when leaving one point and reaching another point, which is its final position.
An example of this can be seen in the image shown below, where the red line represents the displacement of a body that left point A and arrived at point B. The blue dotted line represents the distance traveled and refers to the total displacement of that body, showing all the distances it covered while walking from point A to point B.
Please help with all three questions
Answer:
The correct answer is D C A
A 1500 kg tractor pulls a 750 kg trailer north and applies a 2250 N force on it. What is the force on the tractor?
Answer:
law of Action and Reaction F = 2250 N
Explanation:
The tractor and the trailer are two bodies that interact, therefore, by the law of Action and Reaction, the force that one applies on the other is equal to the force that the second body (trailer) applies on the first (tractor), but with opposite direction
F = 2250 N
directed from trailer to tractor
Explain the mode of operation of x-ray
Answer:
If x-rays get in touch with our body tissues, they create a picture of a metal film. The high energizing rays are unable to penetrate soft tissue, such as skin and organs and travel through the laser. The places where the x-rays pass soft tissues are Black areas of an X-ray.
Answer:
Explanation:
Mode of Operation: In the X-ray tube a Low voltage high p.d is applied between the hot cathode and the anode. Electrons are emitted from the cathode and are accelerated to an extremely high speed. ... They are produced by increasing the p.d. between the cathode and anode.
if something is frictionless does it have thermal energy
Answer:
No
Explanation:
because there is no pressure
Describe the processes that take place inside the nucleus for the following decays; Beta- decay and Beta+ decay.
Answer:
Explanation:
(a) Electron Emission (Beta- decay):
When an unstable nucleus decays by the emission of Beta- particle, its charge number ‘Z’ increases by 1 but, its mass number ‘A’ remains unchanged. The transformation is represented by the equation:
[tex]_zX^A\ -------->\ _{Z+1}Y^A\ +\ _{-1}e^0[/tex]
It is called ‘Negative Beta Decay’. It is more common than alpha decay.
Example:
[tex]_6C^{14}\ -------->\ _{7}N^{14}\ +\ _{-1}e^0[/tex]
Note:
There are no electrons in a nucleus so, with the emission of a particle, one of the neutrons is converted to a proton and an electron.
[tex]_0n^1\ --------->\ _1P^1\ +\ _{-1}e^0[/tex]
(b) Positron Emission (Beta+ decay):
When an unstable nucleus decays by the emission of the positron, its charge number ‘Z’ decreases by 1 but, its mass number ‘A’ remains unchanged. The transformation is represented by the equation:
[tex]_zX^A\ -------->\ _{Z-1}Y^A\ +\ _{+1}e^0[/tex]
Examples:
[tex]_{15}P^{30}\ -------->\ _{14}Si^{30}\ +\ _{+1}e^0[/tex]
Note:
Inside the nucleus, only a proton can be transformed into a neutron with the emission of a positron (anti-particle of electron)
[tex]_1P^1\ -------->\ _0n^1\ +\ _{+1}e^0[/tex]