Answer:
40 hours
Explanation:
in 20 hours, 1/2 will decay
in 40 hours, 1/4 will decay
therefore, 40 hours
What causes moons to orbit planets and  planets to orbit stars
Answer:Orbits are the result of a perfect balance between the forward motion of a body in space, such as a planet or moon, and the pull of gravity on it from another body in space, such as a large planet or star. An object with a lot of mass goes forward and wants to keep going forward; however, the gravity of another body in space pulls it in.
Explanation:
if tje object is placed pf the focus of a concave mirror the image is formed....
Answer:
when object is kept at focus then image will form at infinity
Explanation:
virtual erect highly diminished image will be formed and it is used in the lense in galilean telescope
13. A glass of water left in the sun becomes warm. Estella adds ice to the water to make
it cool. What energy change occurs when ice is added to the warm drink?
Answer:
second
Explanation:
second
Anyone able to help with these questions, will give brainliest to first correct anwser
Answer:
b
Explanation:
I did this question earlier
The heat from the sun travels to Earth___
A. In high-frequency waves
B.In low frequency-waves
C.Through the movement of molecules
D.By conduction and convention
Answer:
a in high frequency waves
Explanation:
because of the thermal radiation from the sun
Answer:
The answer is B, "In low frequency-waves"
Explanation:
I got this right on my lesson! Have a great day! (-;
001)
9. A ball is rolled at a velocity of 12 m/s. After 36 seconds, it comes to a stop. What is the acceleration of the ball?
Answer:
0.33333333333
Explanation:
a = v/t
= 12/36
= 1/3
= 0.3333
Answer:
3
Explain
36/12
The location where an earthquake begins
A. Strike-Slip fault
B. Epicenter
C. Focus
D. Seismogram
Answer:
b
Explanation:
the location where an earthquake begin is called
How does the value and direction of the restoring force change as the spring constant or displacement is changed?
Answer:
The effect of gravity is only to shift the equilibrium point, so at equilibrium (at rest), a vertical spring will be extended as compared with the same spring in a horizontal position. But this does not affect the period.
As the spring constant or displacement is changed, the value and direction of the restoring force change, and they are always toward the equilibrium position of the spring when it is stretched.
What is the significance of the restoring force?When an object is relaxed or stretched, it is responsible for returning it to its original equilibrium position, such as a spring when stretched, and the force is directly proportional to the displacement and acts in the opposite direction of the displacement, the restoring force is responsible for the oscillations and waves, and its properties.
Hence, as the spring constant or displacement is changed, the value and direction of the restoring force change, and they are always toward the equilibrium position of the spring when it is stretched.
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32) In an electrical circuit the current is measured in
A) amps using an ammeter.
B) amps using a voltmeter.
C) volts using an ammeter.
D) volts using a voltmeter.
Answer:
A) amps using an ammeter.....
Need help as fast as possible please
I will mark BRAINLIST only for correct answers babes :)
Thank you!
pleaseeeeeeeeee helpppppppppppppppp
How does an air mattress protect a stunt person landing on the ground after a stunt?
Answer:
a) It reduces the kinetic energy loss of the stunt person.
An air mattress acts as a cushion of gas between the stunt person and the ground, absorbing part of the shock if the action person falls.
What is air mattress?An air mattress is an inflated mattress composed of polyvinyl chloride (PVC) and textile-reinforced urethane plastic and rubber. It is also known as an airbed or even a blow-up bed. Deflated mattresses may be compressed and transported and stored in a tiny size.
An air mattress acts as a cushion of gas between the stunt person and the ground, absorbing part of the shock if the action person falls or if it is thrown from a great height. This shields the stunt performer from catastrophic dangers like shattered bones or concussions.
Therefore, an air mattress acts as a cushion of gas between the stunt person and the ground, absorbing part of the shock if the action person falls.
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Which vector is the sum of the vectors shown below?
please please please hellpppppppp!!!!!!
Answer:
The Answer is A
Explanation:
What is the blank? (physics)
The total energy of a system is equal to the energy added to the system plus the work and the ____ that is produced.
Answer:
Heat???
Sorry I am not at all sure
An electric iron is connected to the mains power supply of 220 V. When the electric iron is
adjusted at 'minimum heating' it consumes a power of 360 W but at 'maximum heating' it takes a
power of 840 W. Calculate the current and resistance in each case.
Answer:
Given: V = 220V, Pmin = 360W, Pmax = 840W
For minimum heating case:
We know that
Pmin = VI
360 = 220 X I
I = 1.63 amp
R = V/I
R = 220/1.63
R = 134.96ohms
For maximum heating case:
We know that
Pmax = VI
840 = 220 X I
I = 3.81 amp
R = V/I
R = 220/3.81
R = 57.74 ohms
A man who has type B blood (genotype: BB) is married to a woman with type O blood. What blood type will their children have? blood typing
The brakes of a lorry are in a poor condition
What effect will the condition of the brakes have on thinking distance and the braking
distance of the lorry?
Answer:
friction
Explanation:
Her brakes will squeak and possibly slide or skid on concrete due to her brakes.
BUT it really depends on the condition of the wheels. Now it matters on the surface as well. Has the road been eroded? what has happened with her brakes? and what texture are the wheels? can seismic waves travel through them?
Answer:
thinking distance stays the same and the braking distance increases
AQA Approved.✅
Explanation:
when you come out of a river you feel cold. why?
Answer:
the wind
Explanation:
2.5 x 103 kilogram truck with rubber tires moves through a 120 meter radius turn on a dry asphalt surface.
a. Determine the force of friction acting on the truck's tires during the turn.
b. Calculate the maximum speed with which the truck could have made this turn.
Answer:
a. The friction force acting on the truck's tires during the turn, is approximately 20,875 N
b. The maximum velocity with which the truck could make the bend is approximately 31.654 m/s
Explanation:
The given parameters of the truck are;
The mass of the truck, m = 2.5 × 10³ kg
The tire material = Rubber
The radius of the turn the through which the truck moves = 120 meters
The material and condition of the surface = Dry asphalt
a. The coefficient of friction of rubber tires on dry asphalt, μ ≈ 0.85 (researchgate (internet source))
The weight of the truck, W = m × g
Where;
m = The mass of the truck = 2.5 × 10³ kg
g = The acceleration due to gravity = 9.8 m/s²
∴ W = 2.5 × 10³ kg × 9.8 m/s² = 24,500 N
The force of friction acting on the tires, [tex]F_f[/tex] = W × μ
∴ [tex]F_f[/tex] = 24,500 N × 0.85 ≈ 20,875 N
The friction force acting on the truck's tires during the turn, [tex]F_f[/tex] ≈ 20,875 N
b. The centrifugal force the truck observes while turning through the bend, 'F', is given as follows;
F = m·v²/r
Therefore, the maximum velocity with which the truck could make the bend, 'v', is given when fiction force, '[tex]F_f[/tex]', is equal to the centripetal force, F
When [tex]F_f[/tex] = F, we have;
W × μ = m·v²/r
∴ 20,875 N = 2.5 × 10³ kg × v²/(120 m)
∴ v² = 20,875 N × (120 m)/(2.5 × 10^3 kg) = 1002 m²/s²
v = √(1002 m²/s²) ≈ 31.654 m/s
The maximum velocity with which the truck could make the bend, v ≈ 31.654 m/s
According to this question;
The mass of the truck (m) = 2.5 × 10³ kgThe radius of the turn = 120mThe coefficient of friction of rubber tires on dry asphalt, μ ≈ 0.85QUESTION 1:
Weight of the truck (W) = m × gWhere;
m = mass of the truck = 2.5 × 10³ kgg = acceleration due to gravity = 9.8 m/s²W = 2.5 × 10³ kg × 9.8 m/s² = 24,500 NThe force of friction acting on the tires, = W × μ= 24,500 N × 0.85 ≈ 20,875 NThe force of friction acting on the truck's tires during the turn = 20,875 NQUESTION 2:
Centrifugal force of the truck can be calculated as follows: F = mv²/rHowever, force of friction (Ff) is equal to centripetal force (F). That is;W × μ = m·v²/r20,875N = 2.5 × 10³ kg × v²/(120 m)v² = 20,875 × 120/2.5 × 10³ = 1002 m²/s²v = √1002 = 31.654m/sThe maximum velocity with which the truck could make the turn = 31.654 m/s.Learn more about force of friction at: https://brainly.com/question/4230804?referrer=searchResults
if a circuit has 3 A of current and a 5 ohm resistor, how many volts are powering the circuit
Answer:
Given =
Current = 3 A
Resistance = 5 ohm
Solution =
By Ohm's Law
R = V/I
V = R x I
V = 5 x 3
V = 15 volts. Answer
write down the expressions for the heat produced per second in a resistor in terms of current and resistance
Answer:
Heat,[tex]H=I^2 R[/tex]
Explanation:
Let H be the heat produced
Time, t=1 sec
I=Current
R=Resistance of resistor
We have to write down the expressions for the heat produced per second in a resistor in terms of current and resistance.
We know that
Heat, [tex]H=I^2 Rt[/tex]
Using the formula
Heat,[tex]H=I^2R\times 1[/tex]
Heat,[tex]H=I^2 R[/tex]
Hence, the the expressions for the heat produced per second in a resistor in terms of current and resistance is given by
Heat,[tex]H=I^2 R[/tex]
Write two characteristics of an educated society
Answer:
Different and better?
Explanation:
i dont think that helps lol
An educated person has the ability to think clearly and independently and has good judgement.
What is Education?Education is defined as purposeful activity directed towards achieving some objective, such as the dissemination of knowledge or the promotion of skills and character traits, whose aims include the development of understanding, rationality, kindness and honesty.
There are three main types of education which are as follows:
Formal, Informal and Non-formal.
The specialty of education is that it is pre-determined and pre-planned. It is regular and spatial i.e. time bound and regulated by the institutional. Proper education improves people's understanding of the world around them which make them less susceptible to the influence of others
Thus, an educated person has the ability to think clearly and independently and has good judgement.
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Newton’s first law of motion states that an object's motion remains the same unless a force acts upon it. What would be an example of this law in action?
Answer:
A driver breaks suddenly and the passengers are flung forward
what happens as photons of visible light are absorbed by dye molecules?
A 40.0 kg box is placed on a 2.00 m tall shelf. If the box falls off the shelf, what is its kinetic energy as it strikes the ground?
Which frequencies can humans can hear but not mice
Why is an electromagnet used instead of a permanent magnet in magnetic cranes?
Answer:
an electromagnet is a metal which has the ability to turn into a magnet on passing electricity through it .
But once the electric flow is withdrawn the circuit breaks and it no more behaves like a magnet.
but this is not so in permanent magnets
Explanation:
thus electromagnet is used in magnetic cranes bcoz their magnetism can be controlled conveniently.
A 8-kg load stretches an elastic belt 0.02 m. How much will a 12-kg load stretch the belt?
Answer:
0.06
Explanation:
a 6 load will be 0.03 so double it to get the answer which is 0.06
write down the expressions for the heat produced per second in a resistor in terms of potential difference and resistance
Answer:
[tex]H=\frac{V^2}{R}[/tex]
Explanation:
Let H be heat produced per sec
Time, t=1 sec
Resistance of resistor=R ohm
We have to write down the expression for the heat produced per second in a resistor in terms of potential difference and resistance.
We know that
Heat, [tex]H=I^2 Rt=\frac{V^2}{R}t[/tex]
Substitute the value
Then, we get
Heat,[tex]H=\frac{V^2}{R}\times 1[/tex]
[tex]H=\frac{V^2}{R}[/tex]
This is required expression for the heat produced per second in a resistor in terms of potential difference and resistance.
