Every living thing gives off thermal energy in the form of which type of
electromagnetic waves?
O A Visible light
B. Gamma rays
C. infrared
O D. Ultraviolet

Answer:

C. Increase in back emf

Explanation:

As the current through the field winding decreases the field strength also decreases and the back-emf is reduced, as a result the motor speeds up.

When the motor begins to speed-up, an additional back EMF is generated due to induction which reduces armature current. This also results in reduced strength of the field flux. The back emf generated is not enough to reduce the armature current which could stop the acceleration of the motor and the motor further accelerates.

Answer:

Time, t = 4.165 seconds.

Explanation:

Given the following data;

Initial velocity = 60 km/h

Final velocity = 90 km/h

Acceleration = 2 m/s²

Conversion:

60 km/hr to meters per seconds = 60*1000/3600 = 60000/3600 = 16.67 m/s

90 km/hr to meters per seconds = 90*1000/3600 = 90000/3600 = 25 m/s

To find the time, we would use the first equation of motion;

[tex] V = U + at[/tex]

Where;

V is the final velocity.

U is the initial velocity.

a is the acceleration.

t is the time measured in seconds.

Making time, t the subject of formula, we have;

[tex] t = \frac{V - U}{a}[/tex]

Substituting into the equation, we have;

[tex] t = \frac{25 - 16.67}{2}[/tex]

[tex] t = \frac{8.33}{2}[/tex]

Time, t = 4.165 seconds.

Answer:

MA = 1.66, VR = 2,  Efficiency = 83.33%

Explanation:

Given the following

Load = 500N

Effort = 300N

Mechanical Advantage = Load/Effort

MA = 500/300

MA = 5/3 = 1.66

Velocity ratio is the number of pulleyc present in the block and tackle system. Since the pulley is a single movable pulley, then VR = 2

Efficiecncy n = MA/VR * 100%

n = 1.66/2 * 100

n = 166/2

n = 83.33%

hope it is helpful to you

Explanation:

the high heels has a more pressure than flat soles bcoz small area has more pressure than large area.

Answer:

2 more neutrons

Explanation:

To obtain the answer to the question, let us calculate the number of neutrons in carbon–14 and standard carbon (i.e carbon–12). This can be obtained as follow:

For carbon–14:

Mass number = 14

Proton number = 6

Neutron number =?

Mass number = Proton + Neutron

14 = 6 + Neutron

Collect like terms

14 – 6 = Neutron

8 = Neutron

Neutron number = 8

For carbon–12:

Mass number = 12

Proton number = 6

Neutron number =?

Mass number = Proton + Neutron

12 = 6 + Neutron

Collect like terms

12 – 6 = Neutron

6 = Neutron

Neutron number = 6

SUMMARY:

Neutron number of carbon–14 = 8

Neutron number of carbon–12 = 6

Finally, we shall determine the difference in the neutron number. This can be obtained as follow:

Neutron number of carbon–14 = 8

Neutron number of carbon–12 = 6

Difference =?

Difference = (Neutron number of carbon–14) – (Neutron number of carbon–12)

Difference = 8 – 6

Difference = 2

Therefore, carbon–14 has 2 more neutrons than standard carbon (i.e carbon–12)

Answer:

D)7 1/2 or 15/2

Explanation:

Let's calculate Combined resistance of the parallel first

1/Rt= 1/2+1/6=4/6

Rt=6/4 which is also equal with 3/2

Now let's add it with the series one

Rt= 6+3/2

=15/2 And when we put that un a mixed fraction 7 1/2

Answer:

I would not feel fear because I haven't had the physiological arousal necessary to induce that emotional state.

Explanation:

The James-Lange theory is a theory of emotions. According to the James-Lange theory, the emotions of a human occur as a result of the physiological reactions to the surrounding events. His theory is one of the well known psychological theories of emotions.

In the context, I took a medicine that prevented the activation of my sympathetic nervous system and imagined a venomous snake that crawls up my leg, I did not feel any fear as I have not had the emotion or the phycological arousal that is necessary to induce the emotional state. It is according the theory of James-Lange.

Answer:

1 km

Explanation:

Bob travels at one km/h and it takes him one hour to get there.

Answer:h

Explanation:

Answer:

Rifle Momentum=7.77kg*m/s v'= 1.554 m/s

Explanation:

a) m1v1 + m2v2 = m1v1' + m2v2'

0+0 = 0.03*259 + P(rifle momentum)

solve for P

p= 7.77kg*m/s

b) 7.77= 5*v'

v'= 1.554 m/s

The momentum of the rifle just after the bullet is fired is 7.77 kg.m/s and the recoil velocity of the rifle at the time of firing is 1.554 m/s.

Momentum of a particle is the product of the mass of the particle and its velocity. Momentum is a vector quantity. It has both the magnitude and direction of motion. According to the Newton's second law of motion, the rate of change of the momentum is equal to the force acting on the particle which is in motion.

Momentum can be calculated by the general formula

p = m.v

where, p = momentum of the particle,

m = mass of the particle,

v = velocity of the particle.

Rifle Momentum= mass × velocity

P = m × v'

a) m1v1 + m2v2 = m1v1' + m2v2'

0+0 = 0.03 × 259 + P(rifle momentum)

0 = 7.77 + P

P = 7.77kg.m/s

b) p = m × v

7.77= 5 × v'

v'= 1.554 m/s

Learn more about Momentum here:

https://brainly.com/question/24030570

#SPJ2

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]

Answer:

11.86°

Explanation:

Projectile motion is a form of motion where an object moves in parabolic path (trajectory). Projectile motion only occurs when there is one force applied at the beginning on the trajectory, after which the only interference is from gravity.

The range of an object experiencing projectile motion is given by:

R = u²sin(2θ) / g

where u is the initial velocity, θ is the angle with horizontal and g is the acceleration due to gravity

Given that R = 6.8 m, g = 10 m/s², u = 12 m/s.  

R = u²sin(2θ) / g

substituting:

6.8 = 13²sin(2θ) / 10

13²sin(2θ) = 68

sin(2θ) = 0.4024

2θ = sin⁻¹(0.4024)

2θ = 23.73

θ = 11.86°

Answer:

The force that propels a toddler down a slide. The force that causes the moon to revolve around the Earth. The force that keeps Jupiter's moons located around the planet. The force from the moon that causes the tides of the ocean.

Explanation:

Answer:

10seconds

Explanation:

use the formula a=v final_v inital/time

Answer:

d= 637323 meters

t= 360.5 seconds

Answer:

Explanation:

Since the height from which the shell was fired is the same as the height at which it lands (on the ground, to be specific), we will use the range equation. That is the only time you CAN use the range equation (when the initial height and the final height are exactly the same). The range equation is:

[tex]r=\frac{v_0^2sin(2\theta)}{g}[/tex] where v0 is the initial velocity, theta is the angle, and g is the pull of gravity (NOT negative). Filling in:

[tex]r=\frac{(1500)^2sin(9.0*10^1)}{9.8}[/tex] so, doing all that math gives us:

r = 6.4 × 10⁵ meters

Answer:

Period refers to the time for something to happen and is measured in seconds/cycle

Answer:

What is the period of time? 5.62 Seconds

What is the amplitude? 1 Centimeters

Explanation:

it just makes sense

R= 40cm —> R= 0.4 m

P= 2mm —> P= 0.002 m

[tex]V.R = \frac{2πR}{p} = \frac{2 \times 3.14 \times 0.4}{0.002} = 1256[/tex]

I think this is the answer

I hope I helped you

Good luck ^_^

Answer:

Explanation:

First job is to convert 72 km/hr to m/s:

[tex]72\frac{km}{hr}[/tex] × [tex]\frac{1000m}{1km}[/tex] × [tex]\frac{1hr}{3600s}[/tex] = 2.0 × 10¹ m/s

Now to find the acceleration which is

[tex]a=\frac{v_f-v_0}{t}[/tex] and filling in:

[tex]a=\frac{2.0*10^1-0}{11.5}=1.7\frac{m}{s^2}[/tex] That's part a. Part b want to know how far the car can get in 11.5 seconds (because that's the time it takes for the car to get to 72 km/hr). Since we know that the car can get 2.0 × 10¹ meters in 1 second, that means that in 11.5 seconds, the car can get 11.5(2.0 × 10¹) which is 230 meters.

Answer:

it takes 365 days to revolve around the star(sun)

c. aluminium

d. it cannot travel through glass

e. mass of 55kg, takes 25s to gain a height of 15m

Answer:

the acceleration of the elevator is increasing

Explanation:

For this exercise we propose the solution using Newton's second law

         F -W = m a

         F = m (g + a)

If the net force increases, it implies that the acceleration of the elevator is increasing, since the acceleration of gravity is constant as the ascent is accelerating.

The amount of energy required for a unit mass of a substance to undergo a phase change from liquid to gas.

Answer:

C. More of the heat is transferred to the kinetic energy of the copper atoms than to the kinetic energy of the water molecules.

Explanation:

Both equal masses of water and copper were heated at the same temperature. Since copper is a good conductor of heat compared to water, its  absorbs more heat. Which in-turn increases the rate of vibrations of the atoms in the copper mass, thus increasing their kinetic energy.

In the case of water, its molecules displaces one another after being heated to a higher temperature compared to neighboring molecules. So that the heated molecule becomes less dense and floats to the surface of water.

This property of copper makes it to be heated to a higher final temperature than the water.

Answer: See explanation

Explanation:

From the information given, we are informed that an instrument rated pilot is planning a flight under IFR on July 10, this year.

It should be noted that before conducting the flight, the pilot must have performed and logged the prescribed tasks and repetitions that are required for instrument currency no earlier than January, 10 for the year.

Answer:

x,y

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fif

hofdhDJiyfuID pork chop it off the bus to school today I am not a mixture of my favorite thing in life that is the best of the day before

Answer:1200

Explanation:

F=ma =m(Vf-Vi)/t

F=120(25-5)/2 =1200N

Answer:

[tex]f = m \frac{v1 - v2}{t} \\ = 120 \times \frac{25 - 5}{2} \\ = 120 \times 10 \\ = 1200N \\ thank \: you[/tex]