Answer:
The sun uses hydrogen for nuclear fusion.
Answer:
Hydrogen
Explanation:
is acting on an object that is constrained to move along the x-axis. If the force moves the object 3m, from the origin, what is the potential energy difference due to this force acting on the object
Answer:
U = - ∫ F dx
U = - 3F₀
Explanation:
Force and potential energy are related
F = [tex]- \frac{dU}{dx}[/tex]
dU = - F dx
∫ dU = - ∫ F dx
U- U₀ = - ∫ F dx
to solve the problem we must know the form of the force, if we assume that F = F₀ and U₀ = 0 for x = 0
U = - F₀ 3
Students were having a catapult contest, launching a tennis ball with their home built devices. The winner launched a ball at 30 degrees from the ground at 6.0 m/s. How high does the ball go?
Answer:
The height reached by the ball=0.459 m
Explanation:
We are given that
[tex]\theta=30^{\circ}[/tex]
Initial speed, u=6 m/s
We have to find the maximum height reached by ball.
Maximum height reached by ball
[tex]h=\frac{u^2sin^2\theta}{2g}[/tex]
Where [tex]g=9.8m/s^2[/tex]
Substitute the values
[tex]h=\frac{6^2sin^230^{\circ}}{2\times 9.8}[/tex]
[tex]h=\frac{36\times \frac{1}{4}}{2\times 9.8}[/tex]
[tex]h=0.459 m[/tex]
Hence, the height reached by the ball=0.459 m
!!!!!URGENT!!!!!!
A heater raises the temperature of air in a room from 22 °C to 37
°C with the energy of 7500 J. If the mass of the air is 5 kg, the specific heat
capacity of the air would be
A. 25 J kg^-1 °C^-1
B. 50 J kg^-1 °C^-1
C. 100 J kg^-1 °C^-1
D. 75 J kg^-1 °C^-1
Answer:
The specific heat of air is 100 J/kg°C.
Explanation:
mass, m = 5 kg
Temperature change, T' - T = 37 °C - 22 °C = 15°C
heat, H = 7500 J
let the specific heat of air is c.
The formula of heat is
H = m c (T' - T)
7500 = 5 x c x 15
c = 100 J/kg°C
Q011) The Doppler effect a. occurs when the frequency of sound waves received is lower if the wave source is moving toward you than if it's moving away. b. occurs when the pitch of a sound gets lower if the source is receding. c. is the basic explanation for the blue shift of light in our Universe. d. can be applied only to sound waves.
Answer:
Option (c) is correct.
Explanation:
The apparent change in the frequency of light due to the relative motion between the source and the observer is called Doppler's effect.
When the source is moving towards the observer which is at rest, the apparent frequency increases and if the observer is moving away the frequency of sound decreases.
It occurs for both light and sound.
So, to explain the blue shift of light in the universe is due to the Doppler's effect of light.
State any ten reasons why students in Uganda need to study physics.(use examples of the possible technological advancements which can be made using the knowledge of physics)
Answer:
The answer is "physics ".
Explanation:
Physics is the branch of science that addresses the properties of crystalline and its interaction with the fundamental elements of the universe. It covers subjects ranging in quantum mechanics with extremely little ones with quantum mechanics to the whole cosmos. You must be constant whether you like it or not, thus everyone must learn physics, irrespective of whether they're in Uganda, and plenty of other countries should have physics to dare study.
A boy is moving a stone in a horizontal circle by mean of a thread attached to ut. The length if the threads us 1 m and the weight of the stone is 0.02 kg . The maximum tension of the thread can withstand us 1 ×10 ^-4 N. The boy is gradually increasing the speed if rotation. At what speed if the stone does the thread break ?
Answer:
Explanation:
This is a centripetal force problem where tension supplies the centripetal force needed to keep the stone moving in a circular manner. That formula for that is
[tex]F_c=T=\frac{mv^2}{r}[/tex] and filling in what we know:
[tex]1*10^{-4}=\frac{.02v^2}{1}[/tex] and solve that for v:
[tex]v=\sqrt{\frac{1*10^{-4}}{.02} }[/tex] which gives us a velocity of .07 m/s. Anything greater than this will break the string.
As a girl pushes and object across a wood floor she suddenly comes to an area where the floor has been waxed recently making it slippery . What becomes true if the coefficient of kinetic friction
Answer:
This question is incomplete but the completed question is below
As a girl pushes an object across a wood floor, she suddenly comes to an area where the floor has been waxed recently, making it slippery. What becomes true of the coefficient of kinetic friction? A. The coefficient of kinetic friction increases. B. The coefficient of kinetic friction decreases. C. The coefficient of kinetic friction becomes zero. D. The coefficient of kinetic friction becomes negative.
The correct option is B
Explanation:
Coefficient of kinetic friction can be defined as the frictional force resisted by the motion of an object. From the question, it might take the girl to apply a force equivalent to just half that of the weight of the object to overcome friction to keep the object moving on a wood floor. Once she gets to the waxed area, the frictional force reduces, thereby also reducing the coefficient of kinetic friction further. Thus, she will be able to use less than half of the force (equivalent to less than half of the weight of the object) to push the object.
Thus, the correct option is B.
Describe the resistance through a
diode
Explanation:
A diode is an electrical element which offers the flow of current freely in one direction with very less resistance.
The given figure depicts a diode in forward bias, where the p-side and the n-side of the diode are connected to positive and negative terminals respectively. In such a case the current flows from the p-side to n-side of the p-n junction very easily and the value of the current increases rapidly after a certain voltage, this voltage is called threshold voltage.
We can deduce from the graph that the resistance of the diode reduces with increase in voltage. As resistance is given by the formula:
[tex]R=\frac{V}{i}[/tex]
Match the synthetic materials with the processes used to make them.
What is the correct equation for the y axis of object B?
Answer:
[tex]N_B-W_B = 0[/tex]
Explanation:
There are two forces acting on object B. If we consider the law of equilibrium, then the two forces must be equal in magnitude, for the object to remain in equilibrium position:
[tex]N_B = W_B\\\\N_B-W_B = 0[/tex]
Therefore, the correct answer of the given question, from the given choices, is:
[tex]N_B-W_B = 0[/tex]
Question 5 of 10
A 15 N force is applied to an object, which then accelerates at 5.0 m/s2. What
is the mass of the object?
A. 10 kg
B. 20 kg
C. 75 kg
D. 3.0 kg
Hi there!
[tex]\large\boxed{D. \text{ } 3.0 kg}}[/tex]
Use the following equation to solve:
F = ma, where:
F = Force (N)
m = mass (kg)
a = acceleration (m/s²)
Thus:
15 = 5m
15/5 = m
mass = 3 kg
The acceleration of the car with two washers added to the string would be
Answer:
[tex]a=0.33\ m/s^2[/tex]
Explanation:
For washer 2,
v₁ = 0.13 m/s
v₂ = 0.36 m/s
t₁ = 1.92
t₂ = 2.61
We need to find the acceleration of waster 2.
[tex]a=\dfrac{v_2-v_1}{t_2-t_1}\\\\a=\dfrac{0.36-0.13}{2.61-1.92}\\\\a=\dfrac{0.23}{0.69}\\\\a=0.33\ m/s^2[/tex]
So, the acceleration of washer 2 is [tex]0.33\ m/s^2[/tex].
Answer:
.33
Explanation:
Which items did Mendeleev write down on note cards while he was observing
different elements?
A. Buoyancy
B. Density
C. Color
D. Atomic mass
Mendeleev wrote down atomic mass
Answer:
A. Buoyancy.
hope it helps
stay safe healthy and happy..The decrease in the intensity of light over distance, such as with increasing depth in water, is known as ______.
Answer:
Attenuation
Step By step Explanation:
The decrease in the intensity of light over distance, such as with increasing depth in water, is known as ______.
It is called attenuation.
The decraese in the amplitude of the signals is called attenuation.
3. Thekinetic energy of an object of
mass, m moving with a velocity
of 5 ms-t is 25 J. What will be its
Toinetic energy when its velocity
is doubled? What will be its
Icinetic energy ruhen its velocity
is increased three times?
Answer:
1. 100 J
2. 225 J
Explanation:
We'll begin by calculating the mass of the object. This can be obtained as follow:
Velocity (v) = 5 ms¯¹
Kinetic energy (KE) = 25 J
Mass (m) =?
KE = ½mv²
25 = ½ × m × 5²
25 = ½ × m × 25
25 = 25m / 2
Cross multiply
25m = 25 × 2
25m = 50
Divide both side by 25
m = 50 / 25
m = 2 Kg
1. Determination of the kinetic energy when the velocity is doubled.
Mass (m) = 2 Kg
Velocity (v) = double the initial velocity
= 2 × 5 ms¯¹
= 10 ms¯¹
Kinetic energy (KE) =?
KE = ½mv²
KE = ½ × 2 × 10²
KE = ½ × 2 × 100
KE = 100 J
2. Determination of the kinetic energy when the velocity increased three times.
Mass (m) = 2 Kg
Velocity (v) = three times the initial velocity
= 3 × 5 ms¯¹
= 15 ms¯¹
Kinetic energy (KE) =?
KE = ½mv²
KE = ½ × 2 × 15²
KE = ½ × 2 × 225
KE = 225 J
what is the Formula for average velocity?
Answer:
Explanation:
Velocity is related to Displacement.
Average velocity = Displacement / Time difference
A lamp is connected to a 230 V mains supply. A current of 4 A flows through the lamp for 30 seconds.
Answer:
The energy dissipated is 27600 J.
Explanation:
Voltage, V = 230 V
Current, I = 4 A
time, t = 30 s
The energy is given by
E = V I t
E = 230 x 4 x 30
E = 27600 J
define acceleration what it's formula
Answer:
The definition of acceleration is a change in the rate of motion, speed or action.
hope it helps.stay safe healthy and happy..Acceleration is the rate of change of velocity.
[tex]acceleration = \frac{(final \: velocity - initial \: velocity)}{time} \\ or \\ a = \frac{(v - u)}{t} \\ \\ The \: S.I. \: unit \: of \: acceleration \: is \: \frac{m}{ {s}^{2} } \: or \: m {s}^{ - 2} [/tex].
My last year's notes on acceleration is attached. Hope it helps you!!
(c) The metal block had a mass of 1.50 kg
The specific heat capacity of the metal was 900 J/kg °C
Calculate the change in thermal energy of the metal during 240 seconds.
Use the Physics Equations Sheet.
Give your answer in kilojoules.
Answer:56
Explanation: I did the test
orange light has a wavelength of 600nm. calculate the frequency if the speed of light in vacuum
the correct answer is ---- 122
SINGLE CORRECT OBJECTIVE
Question 9
speed of a moving object is said to be uniform if it covers equal distances in equal interva
time.
о O
ghte
O false
Your Answer:
Next
Answer:
True
Explanation:
Formula for speed is;
Speed = distance/time
Now, if an object covers an equal distance in equal time intervals, it means the speed will remain the same.
For example if an object covers 3 m every 1 second it means speed will always be; 3/1 = 3 m/s.
Thus the statement is correct.
which type of image is formed by convex lens on a screen?
Answer:
The type of image formed on a screen by a convex lens is real, enlarged and inverted.
Explanation:
A lens can be defined as a transparent optical instrument that refracts rays of light to produce a real image.
Basically, there are two (2) main types of lens and these includes;
I. Diverging (concave) lens.
II. Converging (convex) lens.
A converging lens refers to a type of lens that typically causes parallel rays of light with respect to its principal axis to come to a focus (converge) and form a real image.
Basically, the type of image formed on a screen by a converging (convex) lens is real, enlarged and inverted because it is usually thick across the middle (causing rays of light to converge) but thin at the lower and upper edges.
the bodies in this universe attract one another name the scientist who propounded this statement
Answer:
It was proposed by Isaac Newton
Explanation:
The law of universal attraction of expression
F = [tex]G \ \frac{m_1m_2}{ r^2}[/tex]G m1m2 / r ^ 2
where G is a constant, m₁ and m₂ are the masses of the bodies and r the distance between them.
It was proposed by Isaac Newton
With this law Newton explained that the force that pulls the moon towards the earth is the same as that which attracts an apple towards the earth
Amy throws a softball through the air. What are the different forces acting on the ball while it’s in the air?
The softball experiences
force as a result of Amy’s throw. As the ball moves, it experiences
from the air it passes through. It also experiences a downward pull because of
.
Answer:
1.the friction of air, gravity2.gravity
Answer:
The softball experiences an applied force as a result of Amy’s throw. As the ball moves, it experiences drag from the air it passes through. It also experiences a downward pull because of gravity.
Explanation:
Plato
Connected to a battery that offers a d.d.p. of 3.0Volts, we have the four lamps, all identical with resistances equal to 2.0 Ohms. The association appears in the figure. Note that the switch is open, so it doesn't pass current in the circuit (it's like an off switch). When the key closes, the lamps come on. Determining the Req of the association and the total current flowing through the circuit, we will find:
Answer:
Option D. 5Ω e 0.6 A
Explanation:
1. Determination of the equivalent resistance.
We'll begin by calculating the equivalent resistance of resistor B and resistor C. This can be obtained as follow:
Resistor B (R₆) = 2 Ω
Resistor C (R꜀) = 2 Ω
Equivalent Resistance (R₆꜀) =?
R₆꜀ = R₆ × R꜀ / R₆ + R꜀ (parallel connection)
R₆꜀ = 2 × 2 / 2 + 2
R₆꜀ = 4 / 4
R₆꜀ = 1 Ω
Finally, we shall determine the equivalent resistance of the circuit. This can be obtained as follow:
Resistor A (Rₐ) = 2 Ω
Equivalent resistance of resistor B and C (R₆꜀) = 1 Ω
Resistor D (Rₔ) = 2 Ω
Equivalent Resistance (R) =?
R = Rₐ + R₆꜀ + Rₔ (series connection)
R = 2 + 1 + 2
R = 5 Ω
Thus, the equivalent resistance of the circuit is 5 Ω
2. Determination of the total current in the circuit.
Potential difference (V) = 3 V
Equivalent resistance (R) = 5 Ω
Total current (I) =?
V = IR
3 = I × 5
Divide both side by 5
I = 3 / 5
I = 0.6 A
Thus, the total current in the circuit is 0.6 A
Summary:
Equivalent resistance = 5 Ω
Current = 0.6 A
Option D gives the current answer to the question.
A ball is thrown vertically upward. As it rises, what happens to its potential energy?
Answer:
Explanation:
As the ball rises, its PE increases because the potential energy is equal to the mass of the ball times gravity times the height of the ball. The higher the height, the higher the PE.
Answer:
According to the law of conservation of energy its kinetic energy is getting converted in to potential energy because of gain in height. So, if the velocity of a ball goes on decreasing when it is thrown vertically upwards. When its velocity becomes zero, its potential energy becomes maximum.
what happens to the force when the distance increases between 2 particales
How does your ear work? 6 mark question
Answer:
It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified. The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate.
It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified. The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate. Explanation:
The Outer Ear
The auricle (pinna) is the visible portion of the outer ear. It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified.
The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate.
The Middle Ear
The vibrations from the eardrum set the ossicles into motion. The ossicles are actually tiny bones — the smallest in the human body. The three bones are named after their shapes: the malleus (hammer), incus (anvil) and stapes (stirrup). The ossicles further amplify the sound.
The tiny stapes bone attaches to the oval window that connects the middle ear to the inner ear. The Eustachian tube, which opens into the middle ear, is responsible for equalizing the pressure between the air outside the ear and that within the middle ear.
The Inner Ear
The sound waves enter the inner ear and then into the cochlea, a snail-shaped organ. The cochlea is filled with a fluid that moves in response to the vibrations from the oval window. As the fluid moves, 25,000 nerve endings are set into motion. These nerve endings transform the vibrations into electrical impulses that then travel along the eighth cranial nerve (auditory nerve) to the brain.
The brain then interprets these signals, and this is how we hear.
The inner ear also contains the vestibular organ that is responsible for balance.
show that pv=nrt has the same unit with energy
Answer:
It is proved.
Explanation:
PV = n R T
where, P is the pressure, V is the volume, n is the number of moles, R is the gas constant, T is the absolute temperature.
Unit of pressure is Pascal= Newton/square meter = [tex][ML^{-1}T^{-2}][/tex]
Unit of volume is cubic meter = [tex][L^{3}][/tex]
So, the unit of P V
[tex][ML^{-1}T^{-2}] \times [L^{3}]\\\\[ML^2T^{-2}}[/tex]
[tex][ML^{2}T^{-2}][/tex]
It is same as the unit of energy.
hence proved.
A stream leaving a mountain range deposits a large part of its load in a __
Answer:
(n) alluvial fan sandbar
Explanation: