plz help i have an exam and i dont understand this

A body initially moving at a constant speed is brought to rest at a uniform rate. Which of the speed time graphs below indicate the motion of the body? *
2 points

Answer:

7 seconds

Explanation:

he went down -28 m/s so 7 times -4 equals -28 m/s which is what he needed to slowness down to 10 m/s

Explanation:

The name of the SI unit for force is NEWTON .

ur statement is false

have a nice day

Answer:

to prevent to much current

Explanation:

in the event of a power surge the circuit breaker will cut the power. this is what people mean when they say "pop" the breaker

(a) 39 V

(b) 7.8 V

(a) Neglecting the internal resistance of the battery, the voltage drop (V) across the battery is found from Ohm's law as follows;

V = IR                -------------------------(i)

Where;

I = current through the battery

R = total resistance of the circuit.

From the question;

I = 0.75A

R = 52.0Ω

Substitute the values of I and R into equation (i)

=> V = 0.75 x 52.0

=> V = 39Volts

Therefore, the voltage drop across the battery is 39 Volts

(b) Since the set of lanterns is connected in series, then the same current flows through each of the lanterns. Also, since the lanterns are identical, the resistance ([tex]R_{L}[/tex]) of each of them is given by the total resistance (R = 52.0Ω) divided by the number of lanterns. i.e

[tex]R_{L}[/tex] = [tex]\frac{52.0}{5}[/tex]

[tex]R_{L}[/tex] = 10.4Ω          [Each lantern has a resistance of 10.4Ω]

The current flowing through them is the same as the current (I = 0.75A) flowing the circuit.

Therefore, using Ohm's law, the voltage drop ([tex]V_L[/tex])across each load (lantern) is

[tex]V_L[/tex] = I x [tex]R_{L}[/tex]

[tex]V_L[/tex] = 0.75 x 10.4

[tex]V_L[/tex] = 7.8Volts

Therefore, the voltage drop across each load is 7.8 Volts

Answer:

Image not full.

Explanation:

From what I can see, Displacement is 175m,

Distance will be = 100 + 50 + the hidden value on the bottom right

Answer:

Answer is 98 joules

Explanation:

P. E=2*9.8*3=98

S.i unit of potential energy ⚡ is joules

So answer is 98 joules

Answer:

True

Explanation:

because they can hold marine organism inside

Answer:

P = 5292 kJ

Explanation:

Given that,

The mass of a person, m = 120 kg

The height of the plane, h = 4500 m

The Gravitational Potential Energy of the person is given by :

P = mgh

Put all the values,

P = 120 kg × 9.8 m/s² × 4500 m

= 5292000 J

or

= 5292 kJ

So, the required gravitational potential energy is 5292 kJ.

Answer:

The process of making alloys involves ( Heating ) pure metals to remove impurities. Then the pure metals are(mixed) with other components. An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by a metallic bonding character.

Explanation:

Answer:

False

Explanation:

Friction is a force exerted by a surface against the motion of a body across its surface. Therefore, friction is a type of contact force only.

Answer:

both

Explanation:

and I'm serious he is literally both

Answer:

C is the correct answer.

Answer:

work done = kinetic energy in a SHM

= 1/2mW²r²

but ; w = v/r

therefore ; w:d = 1/2mv²/r² × r²

= 1/2 mv²

= 1/2 × 2×6²

= 36J

Answer:

1. Formula = distance/time

D= 112.0 meters, time =4 secs

Speed = d/t =112.0/4

= 28m/s

2.Formula = distance/time

D= 1/4 x 16093.44 m

= 402.35m

Time = 15secs

Speed= d/t

= 402.35/15

=26m/s

Answer:

In antiquity, systems of measurement were defined locally: the different units might be defined independently according to the length of a king's thumb or the size of his foot, the length of stride, the length of arm, or maybe the weight of water in a keg of specific size, perhaps itself defined in hands and knuckles.

Systems of Measurement: there are two main systems of measurement in the world: the Metric (or decimal) system and the US standard system. ... The US Standard system uses units that have no predictable relationship to each other. For example, there are 2 cups in a pint, but 4 quarts in a gallon.

Answer:

A. Proton

Explanation:

Given that an electron has a net negative charge equal in magnitude to the charge of a proton (1.602 × 10⁻¹⁹) but having an opposite (negative) sign to that of a proton, and given that like charges (negative to negative) repel and unlike charges attract, an object having;

Greater electron will be negatively charged relative to the other object, to which it is compare, which is a proton will attract the (positively charged) proton

Lesser negative charge compared to the proton; therefore, both objects will be positive, and they will repel each other

We therefore have;

Having greater or less electrons possessed by an object. Can attract or repel a proton

The correct option is option A. proton

Answer:

Explanation:

The vertical component is found in the magnitude of the force times the sine of the angle; the horizontal component is found in the magnitude of the force times the cosine of the angle. Thus:

vertical component = [tex]60.0sin(30.0)=30.0[/tex] and

horizontal component = [tex]60.0cos(30.0)=52.0[/tex]

Answer:

d) All the above

Explanation:

Therefore, as all of the physical quantities have the same SI units, the answer is d) all of the above.

Answer:

Explanation:

If the hippo is laying on the rock, I'm assuming that there is no movement going on at all, in either the hippo or the rock. If no movement occurs, there is no work being done.

Answer:

acceleration

rhymes with accelerator

Explanation:

the increase/decrease or the sudden change in speed and direction of object

Answer:

renewable, you can keep growing corn for it. more fossil fuel can be made by nature but it takes way too long to be considered renewable

Answer:

242.4 V

Explanation:

Applying,

Q = cm(t₂-t₁)................ Equation 1

Where Q = amount of  heat, c = specific heat capacity, m = mass, t₁ = initial temperature, t₂ = final temperature.

But this heat is produced by electrical power

Therefore,

P = Q/t

Where P = Electrical power, t = time

Also,

P = V²/R

Where V = voltage, R = resistance

Therefore

V²/R = Q/t......................... Equation 2

Substitute equation 1 into equation 2

V²/R = cm(t₂-t₁)/t................. Equation 3

Given: R = 250 ohms, m = 4.6 kg, t₁ = 22°C, t₂ = 32°C, t = 15 min. = (15×60) = 900 seconds

Constant: c = 4600 J/kg.°C

Substitute these values into equation 2

V²/250 = 4600(4.6)(32-22)/900

V²/250 = 235.11

V² = 250×235.11

V² = 58777.78

V = √58777.78

V = 242.4 V

Answer: Conduction occurs more readily in solids and liquids, where the particles are closer to together, than in gases, where particles are further apart.

Answer:

conduction occurs when gas becomes liquid.

Answer:

objects with greater mass should have greater inertia

Complete question:

A small 175-g ball on the end of a light string is revolving uniformly on a frictionless surface in a horizontal circle of diameter 1.0 m. The ball makes 2.0 revolutions every 1.0 s. What are the magnitude and direction of the acceleration of the ball?

Answer:

The acceleration of the ball is 78.98 m/s², directed inwards

Explanation:

Given;

mass of the ball, m = 175 g

radius of the circle, r = 0.5 m

angular speed of the ball, ω = 2 rev/s

The magnitude of the centripetal acceleration of the ball is calculated as follows;

[tex]a_c = \omega^2 r\\\\where;\\\omega \ is \ angular \ speed \ in \ rad/s\\\\a_c = (2\ \frac{rev}{s} \times \frac{2\pi \ rad}{1 \ rev} )^2 \times (0.5 \ m)\\\\a_c =78.98 \ m/s^2[/tex]

The centripetal acceleration is directed inwards.

Complete Question: A horse pulls a cart along a flat road. Consider the following four forces that arise in this situation. (1) the force of the horse pulling on the cart (2) the force of the cart pulling on the horse (3) the force of the horse pushing on the road (4) the force of the road pushing on the horse Suppose that the horse and cart have started from rest; and as time goes on, their speed increases in the same direction. Which one of the following conclusions is correct concerning the magnitudes of the forces mentioned above?

A) Force 1 exceeds force 2.

B) Force 2 is less than force 3.

C) Force 2 exceeds force 4.

D) Force 3 exceeds force 4.

E) Forces 1 and 2 cannot have equal magnitudes.

Answer: B) Force 2 is less than force 3.

Explanation: From the given four forces to be considered, Force 2 is less than Force 3 is correct option.

After evaluating the forces one by one. Force 3 and Force 4 are the same, both have equal magnitude.

And Force 3 is greater than Force 2, i.e., the force of the horse pushing on the road is much higher than the cart pulling the horse. Hence, more forces is required to pull the cart while on the road towards forward direction.

More so, the force of the road pushing on the horse is greater than the force of the cart pulling on the horse.

Answer:

an open circuit (A battery, bulb, wire,switch)

Explanation:

the battery supplies the power the wire carries the current from the battery to the bulb but the circuit is not completed if the switch is not connected (Switch )

Respuesta:

24m

Explicación:

Según la ecuación de movimiento

v = u + en

Dado

Velocidad final v = 12 m / s

velocidad inicial u = 0 m / s

tiempo t = 4s

Sustituir

12 = 0 + 4a

a = 12/4

a = 3 m / s²

Lo siguiente es obtener la distancia;

S = ut + 1 / 2at²

S = 0 (4) + 1/2 (3) (4) ²

S = 3 * 16/2

S = 48/2

S = 24 m

Por lo tanto, la distancia requerida es de 24 m.