Answer:
A
Explanation:
The moving object will accelerate as long as a net force is applied. If a net force is not applied, the object will continue to move at a constant speed along the same path in curved spacetime (due to gravity). If the net force continues the velocity of the object will continue to increase until nearly reaching the limit (speed of light).
Which has greater kinetic energy, a car traveling at 40 mph or a half-as-massive car traveling at 80 mph?
a
-The 40 mph car
-The 80 mph car
-Both have the same kinetic energy
-Neither has kinetic energy
Answer:
The 80 mph car
Because the formula says 1/2 mass but for the velocity it is squared
The unit of area is a derived unit. Why?
Explanation:
area=length(m) ×breadth(m) . The unit of area is expressed in terms of fundamental units m^2.thus it is derived unit
At the local grocery store, you push a 14.5-kg shopping cart. You stop for a moment to add a bag of dog food to your cart. With a force of 12.0 N you now accelerate the cart from rest through a distance of 2.29 m in 3.00 s. What was the mass of the dog food?
Answer:
The mass of the dog food added is 9.03 kg
Explanation:
Given;
mass of the shopping cart, m₁ = 14.5 kg
let the mass of the bag added = m₂
the force applied, F = 12 N
initial velocity of the cart-bag system, u = 0
distance traveled by the system, d = 2.29 m
time of motion of the system, t = 3.0 s
The acceleration of the system is calculated as;
[tex]d = ut + \frac{1}{2} at^2\\\\2.29 = 0 + (\frac{1}{2} \times 3^2)a\\\\2.29 = 4.5 a\\\\a = \frac{2.29}{4.5} \\\\a = 0.51 \ m/s^2[/tex]
The total mass of the system (M) is calculated as follows;
F = Ma
M = F/a
M = (12)/(0.51)
M = 23.53 kg
The mass of the dog food added is calculated as;
m₂ = M - m₁
m₂ = 23.53 kg - 14.5 kg
m₂ = 9.03 kg
DO U KNOW CARRYMINATI
A HIGH SPEED TRAIN IS 180M LONG AND IT IS TRAVELLING AT 50M/S.HOW LONG WILL IT TAKE TO PASS A PERSON STANDING AT A LEVEL CROSSING?
B-HOW LONG WILL IT TAKE TO PASS COMPLETELY THROUGH A STATION WHOSE PLATFORMS ARE 220M IN LENGTH?
Answer:
a. Time = 3.6 seconds
b. Time = 4.4 seconds
Explanation:
Given the following data;
Distance = 180 m
Speed = 50 m/s
a. To find the time;
Speed can be defined as distance covered per unit time. Speed is a scalar quantity and as such it has magnitude but no direction.
Mathematically, speed is given by the formula;
[tex]Speed = \frac{distance}{time}[/tex]
Making time the subject of formula, we have;
[tex]Time = \frac{distance}{speed}[/tex]
Substituting into the equation, we have;
[tex]Time = \frac{180}{50}[/tex]
Time = 3.6 seconds
b. Distance = 220 meters
Speed = 50 m/s
To find the time;
[tex]Time = \frac{distance}{speed}[/tex]
Substituting into the equation, we have;
[tex]Time = \frac{220}{50}[/tex]
Time = 4.4 seconds
In this experiment, the ______ was intentionally manipulated. This was the independent variable.
A. fan speed
B. mass
C. acceleration
Answer:
Fan speed
Explanation:
because is the dependent variable
Please help!!!!! I will give brainliest. Describe four examples of acceleration you see during your day. Choose an object that is slowing down, one that is speeding up, one that is moving at a constant speed but changing direction, and one that is moving at a constant velocity with zero acceleration.
When the brake is applied to the car and comes to rest after some time is an example of an object that is slowing down.
What is acceleration?The rate of change of velocity with respect to time is known as acceleration. According to Newton's second law, the eventual effect of all forces applied to a body is its acceleration.
1. When the brake is applied to the body and comes to rest after some time is an example of an object that is slowing down.
2. When a person accelerates the car and the velocity is increasing is an example of speeding up.
3. An object moves in a circular motion moving at a constant speed but changing direction,
4. Acceleration is the rate of change of velocity. If the change in the velocity is constant the acceleration is zero is an example of moving at a constant velocity with zero acceleration.
To learn more about acceleration, refer to the link;
https://brainly.com/question/2437624
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Select the correct answer.
Which quantity is a vector quantity?
ОА. .
acceleration
OB.
mass
OC.
speed
O D.
volume
Reset
Next
Answer:
acceleration is the vector quantity because it depends on particular direction and has magnitude
Which energy store is increased when an object is heated?
Answer:
Kinetic Energy
Explanation:
when is the acceleration of body is positive negative and zero?
Answer:
【 In vector form , if angle between velocity vector and acceleration vector is less than 90° and greater than 0° then it is positive acceleration and if it is less than 180° and greater than 90° then it is negative acceleration. If there is no acceleration vector then it is called zero acceleration. 】
in a series circuit, how does the voltage supplied by the battery compare to the voltages on each load?
Answer:
In a series circuit, how does the voltage supplied by the battery compare to the voltage on each load? The voltage of the battery is equal to the voltage of each load added together. ... The voltage across the two resistors must both have the same voltage of the battery.
Explanation:
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Answer:
The voltage of the battery is equal to the voltage of each load added together. The voltage across the two resistors must both have the same voltage of the battery.
>3
What is an example of a series circuit
Answer:
Explanation
The most famous and common example is Christmas tree lights. You can't tell easily by looking at them whether they are in series or parallel. But you sure know the difference when one of them burns out. When that happens, the whole string goes dead. No matter what you do (other than find out which bulb burned out) will not fix the problem.
Another example is anything that is temperature controlled. For example a furnace is controlled by a thermostat. When the room temperature reaches a certain point, the thermostat is constructed in a certain way so that it forms an open circuit and no current can flow through it. The furnace motor turns off and the furnace stops pumping hot air into a room.
Which type of wave causes particles of matter to vibrate in a direction
perpendicular to the direction of its motion?
O A. Sound
B. Transverse
C. Longitudinal
D. Compression
Answer:
C.) Longitudinal
HELPPP ILL GIVE BRAINLIST
Answer:
1= Kidneys
2= Ureters
3=Bladders
4=Urethra
Explanation:
Functions of kidney: Regulations of water balances, excretions of nitrogenous wastes(urea)
Functions of Liver: Detoxifications, protein synthesis
Functions of Skin: Temperature regulations, Metabolic functions, Excretion
Functions of lungs: Respiration, Water balance regulations
Tip: If you want faster and correct answers you should label your questions under the correct subject.
The isotope used to remove cancer malignancy cell the given options are a. Strontium 89 b. Uranium 238 c. Carbon 14 d. Chlorine 37.......... can anyone tell me the ans plzz
Answer:
B. Uranium 238.
Explanation:
It is radioactive and can be used to treat cancer in the form of radiotherapy
with respect to air the refractive index of ice is 1.31 and that of rock salt is 1.54 calculate the refractive index of rock salt with respect to ice
Answer:
1.17
Explanation:
Given that,
The refractive index of ice wrt air = 1.31
The refractive index of rock salt wrt air = 1.54
We need to find the refractive index of rock salt with respect to ice.
We know that,
refractive index = (speed of light in air or vaccum)/( speed of light in that medium)
So,
The speed of light in ice = c/(1.31)
The speed of light in rock salt = c/(1.54)
So, the refractive index of rock salt with respect to ice is :
[tex]\mu=\dfrac{1.54}{1.31}\\\\=1.17[/tex]
So, the required refractive index of rock salt wrt ice is 1.17.
If the amplitude of a sound wave is increased by a factor of four,how does the energy carry by the sound wave in each time interval change?
Answer:
The energy will be increased by a factor 16
Explanation:
Mathematically, we have it that the energy carried by the sound wave is directly proportional to the square of the amplitude
So we have it that;
E = k * A^2
where E is the wave energy
K is the constant value
A is the amplitude value
So;
If E1 = k * (A1)^2
E2 = k * (A2)^2
But A2 = 4A1
E2 = k * (4A1)^2
E2 = k * 16(A1)^2
Divide E2 by E1
E2/E1 = k/k * 16(A1)^2/(A1)^2
E2/E1 = 16
E2 = 16 * E1
so simply, the energy will be increased by a factor of 16
describe 2 ways you could increase the efficiency of a household central heating system
Answer:
Arrange an annual service. Treat your boiler like your car. ...
Keep your boiler clean. ...
Bleed your radiators. ...
Top up the pressure. ...
Use a Powerflush. ...
Insulate your pipes. ...
Turn the heating on. ...
If all else fails…
Explanation:
A car travelling along a straight road has kinetic energy of 180 kJ. The brakes are applied, and it is brought to rest over a distance of 60 m. What is the average force of the car breaks?
A. 3 N
B. 3000 N
C. 10,800 N
Answer:
Given,
w= 180J
s=60m
W=F×s
180=F×60
180/60=F
F= 3 N
"" damped force equation ""
Answer:
In many vibrating systems the frictional force Ff can be modeled as being proportional to the velocity v of the object: Ff = −cv, where c is called the viscous damping coefficient.
What are the poles of a bar magnet.is it North West South or east.
Answer:
One end of any bar magnet will always want to point north if it is freely suspended. This is called the north-seeking pole of the magnet, or simply the north pole. The opposite end is called the south pole.
Explanation:
Answer:
North Pole and South Poles
Explanation:
There is no east or west in a magnetic field of a magnet. The magnetic field lines comes from North pole to south pole.
A 52 kg child on a swing is travelling at 6 m/s . What is his gravitational potential energy if he has 1000 J of the mechanical energy?
Answer:
The correct answer is "64 J".
Explanation:
The given values are:
Mass,
m = 52 kg
Velocity,
v = 6 m/s
Mechanical energy,
= 1000 J
Now,
The gravitational potential energy will be:
⇒ [tex]P.E=1000-\frac{1}{2}mv^2[/tex]
[tex]=1000-\frac{1}{2}\times 52\times (6)^2[/tex]
[tex]=1000-26\times 36[/tex]
[tex]=1000-936[/tex]
[tex]=64 \ J[/tex]
which of the following items has the most inertia while at rest
Answer:
wats the following items
Match the reactants with the products. zinc sulfate + copper aluminum chloride + copper copper oxide copper + water copper sulfate + oxygen
Answer:
The Reactants Products
Copper sulfate + zinc → Zinc sulfate + copper
aluminum + copper chloride → Aluminum chloride + Copper
Copper + Oxygen → Copper oxide
Explanation:
The Reactants Products
Copper sulfate + zinc Zinc sulfate + copper
aluminum + copper chloride Aluminum chloride + Copper
Copper + Oxygen Copper oxide
First reaction can be described as a single replacement reaction
Second reaction is also a single replacement reaction just like the first reaction
The third is a synthesis reaction ( i.e. reaction in which elements combine to form single compound )
a) How much electrical energy, in joules, does a 1000W space heater consume when it runs for 8h? (b) How much energy is that in kilowatt hours? (c) Calculate the cost of using this heater if 1kWh costs 0.5 dollars.
Answer:
a. Energy = 28800000 Joules
b. Energy = 8 Kwh
c. Cost = $4
Explanation:
Given the following data;
Power = 1000 Watts
Time = 8 hours
Cost = $0.5 per KWh
Conversion:
1 hour = 60 * 60 = 3600 seconds
8 hour = 8 * 3600 = 28800 seconds
a. To find much electrical energy, in joules;
Energy = power * time
Energy = 1000 * 28800
Energy = 28800000 Joules
b. To find how much energy is that in kilowatt hours;
Energy = power * time
Energy = 1000 * 8
Energy = 8000 Watt-hour = 8000/1000 = 8 Kwh (1 Kilowatts is equal to 1000 watts).
c. To calculate the cost of using this heater;
Cost = 8 * 0.5
Cost = $4
A car takes a full round of journey in a roundabout with constant speed, as the driver got confused with the route. Can we consider it as a uniform motion? Why?
Answer: The given statement is True
Explanation:
A uniform motion is defined as the motion where an object is moving at a constant speed.
A non-uniform motion is defined as the motion where an object keeps changing its position and does not move at a constant speed.
We are given:
A car takes a full round of journey in a roundabout with constant speed
As the speed remains constant in a circular path, it is considered a uniform motion.
Hence, the given statement is True
If a driver makes contact with a steering wheel during a 35 mph crash, she comes to rest in about Δ=15 ms. If, during an identical crash, the driver makes contact with an air bag, she comes to rest in about Δ=110 ms. What is the ratio of the force exerted by the steering wheel to the force exerted by the air bag on the driver?
Answer:
The ratio of forces is 22 : 3.
Explanation:
Case I:
initial velocity, u = 35 mph
final velocity, v = 0
time, t = 15 ms
Case II:
initial velocity, u = 35 mph
final velocity, v = 0
time, t' = 110 ms
let the mass is m.
According to the Newton's second law, the force is given by the rate of change of momentum.
So
[tex]F =\frac{m(v-u)}{t}\\\\F'= \frac{m(v-u)}{t'}\\\\So, \frac{F}{F'} =\frac{t'}{t}\\\\\frac{F}{F'}=\frac{110}{15}=22:3[/tex]
Ball X has a mass of 8kg and is moving toward ball Y (which is sitting still) at 2m/s. After they collide, ball X is
sitting still. How fast is ball Y moving after the collision if it has a mass of 4kg?
Answer:
v = 4 m/s
Explanation:
Given :
Ball X :
Mass, m1 = 8kg ;
Initial Velocity, u1 = 2 m/s
Final velocity, v1 = 0
Ball Y:
Mass, m2 = 4kg ;
Initial Velocity, u2 = 0 m/s
Final velocity, v2 = v
(m1u1 + m2u2) = (m2v2 + m1v1)
(8*2 + 4*0) = (4*v + 4*0)
16 + 0 = 4v + 0
16 = 4v
v = 16 / 4
v = 4 m/s
Answer:
Explanation:
This is the Law of Momentum Conservation which for us looks like this:
[tex][m_xv_x+m_yv_y]_b=[m_xv_x+m_yv_y]_a[/tex] and that should look familiar to you if this is what you are doing in physics. Filling in our particular info:
[(8.0 × 2.0)+ (4.0 × 0.0)] = [(8.0 × 0.0) + (4.0v)] and
16 + 0 = 0 + 4.0v and
16 = 4.0v so
v = 4.0 in the direction of ball X
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The current in a resistor is 5 A and the voltage between its terminals is 40 V. Calculate the resistance.
An iron wire has a resistance of 24 Ω. If the voltage across its ends is 12 V, calculate the current in the wire.
Answer:
1=8 ohms 2=0.5 Amps
Explanation:
A ship anchored at sea is rocked by waves that have crests Lim apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Question: A ship anchored at sea is rocked by waves that have crests 100 m apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Answer:
0.7 Hz
Explanation:
Applying,
v = λf............... Equation 1
Where v = velocity of the wave, f = frequency fo the wave, λ = wavelength of the wave
make f the subject of the equation
f = v/λ................. Equation 2
From the question,
Given: v = 70 m/s, λ = 100 m ( distance between successive crest)
Substitute these values into equation 2
f = 70/100
f = 0.7 Hz
Hence the frequency at which the wave reach the ship is 0.7 Hz
