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3 years ago

Figure one, voltmeters

Physics

1 answer:

slava [35]3 years ago

6 0

Answer:

(i) Half

(ii) 3 V

(iii) V₁

Explanation:

(i) The given parameters are;

The circuits have identical resistances

The number of resistors in circuit 1 = 1 resistor

The number of resistors in circuit 2 = 2 resistors

Let 'R' represent the value of each resistor, we have;

The total resistance of circuit 1 = R Ohm

The total resistance of circuit 3 = 2·R Ohm

∴ The total resistance of circuit 1 = (1/2) × The total resistance of circuit 3

∴ The resistance of circuit 1 is <u>half</u> the resistance of circuit 3

(ii) The potential difference of each cell, V = 1.5 volts

The number of cells in circuit 2 = 2 cells

The total potential difference of the cells of circuit 2 = 2 × 1.5 volts = 3 × volts = 3 V.

The voltmeter reading = The potential difference across the cell or cells it is applied

∴ The voltmeter reading on voltmeter, V₂, applied across the cells of circuit 2 = 3 V

(iii) The voltmeter reading V₁ = 1.5 V

The voltmeter reading V₂ = 3 V

The voltmeter reading V₃ = 4.5/(2·R) × R = 2.25 V

Therefore, the voltmeter reading with the smallest volt, is V₁ = 1.5 V

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q = I x t

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Substitute 0.500 x 10⁻³ A for I and 0.750 s for t in the above equation,

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4 years ago

Why are chemicals and hot objects never placed directly on the balance pan?

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3 years ago

A ball is thrown upward with a speed of 28.2 m/s.A. What is its maximum height?B. How long is the ball in the air?C. When does t

Ede4ka [16]

Answer:

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(B) Time spent by the ball on air is 5.76 s

Explanation:

Given;

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u² = 2gh

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(B) Time spent by the ball on air

Time of flight = Time to reach maximum height + time to hit ground.

Time to reach maximum height = time to hit ground.

Time to reach maximum height is given by;

v = u - gt

u = gt

$t = \frac{u}{g}$

Time of flight, T = 2t

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v² = u² - 2gh

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3 years ago

A 125 W motor accelerates a block along a level, frictionless surface at an average speed of 5.0

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Answer:

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Explanation:

Given parameters:

Power of the motor = 125W

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Unknown:

Force supplied to the motor = ?

Solution:

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Work done = Force x distance

Also,

Work done = Power x time

So;

Force x distance = Power x time

since force is the unknown;

Force = $\frac{Power x time}{distance}$

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Force = $\frac{Power}{speed}$

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