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3 years ago

A milliammeter has an internal resistance of 5ohms and

Physics

1 answer:

Vikentia [17]3 years ago

7 0

Answer:

Rs = 0.02008 Ω = 20.08 mΩ

Explanation:

The range of an ammeter can be increased by connecting a small shunt resistance to it in a series combination. This shunt resistance can be calculated by the following formula:

$Rs = \frac{I_gR_g}{I - I_g}$

where,

$R_s$ = value of shunt resistance = ?

$I_g$ = current range of ammeter = 20 mA = 0.02 A

I = Required range of ammeter = 5 A

$R_g$ = Resistance of ammeter = 5 ohms

Therefore,

$R_s = \frac{(0.02\ A)(5\ ohms)}{5\ A-0.02\ A}$

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What is the sequence of energy transformations from the moment the ball is dropped to the moment the board is bent to its maximu

Mila [183]

Answer:

Explanation:

Transformation of energy involves conversion of energy from one form to another for example our movement around involves the conversion of chemical energy stored in the food we eat to other forms of energy such as kinetic energy for the movement, electrical energy in the neurons for impulses and others

The ball posses gravitational potential energy since it is held at a displacement to the ground ( zero point) and when released, the gravitational potential energy is converted to kinetic energy which leads to the fall of the ball until it is at zero displacement to the earth. The board likewise when bent to its maximum extent stored elastic potential energy as a result of the partial displacement of its constituent particle provided it is not stretch beyond its elastic limit which can lead to deformation of the board and the elastic potential energy lost.

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3 years ago

What is the approximate value of the gravitational force between a 73 kg astronaut and a 7.1×104 kg spacecraft when they're 89 m

Luden [163]

Answer:

$F = 4.3671 * 10^{-8}\ Newtons$

Explanation:

The gravitational force between two corpses is given by the following equation:

$F = GMm/d^2$

Where F is the force, G is the gravitational constant

( $G = 6.67408*10^{-11}\ m^3kg^{-1}s^{-2}$ ), M and m are the masses of the corpses and d is the distance between them.

So we have that:

$F = 6.67408*10^{-11} * 7.1*10^4 * 73/89^2$

$F = 4.3671 * 10^{-8}\ Newtons$

5 0

3 years ago

A tennis racket hits a tennis ball with a force of F=at−bt2, where a = 1290 N/ms , b = 330 N/ms2 , and t is the time (in millise

denpristay [2]

Answer:

The resulting velocity of the ball after it hits the racket was of V= 51.6 m/s

Explanation:

m= 55.6 g = 0.0556 kg

t= 2.8 ms = 2.8 * 10⁻³ s

F= 1290 N/ms * t - 330 N/ms² * t²

F= 1024.8 N

F*t= m * V

V= F*t/m

V= 51.6 m/s

6 0

3 years ago

The L-ft ladder has a uniform weight of W lb and rests against the smooth wall at B. θ = 60. If the coefficient of static fricti

Colt1911 [192]

This question is incomplete, the complete question;

The L-ft ladder has a uniform weight of W lb and rests against the smooth wall at B. θ = 60. If the coefficient of static friction at A is μ = 0.4.

Determine the magnitude of force at point A and determine if the ladder will slip. given the following; L = 10 FT, W = 76 lb

Answer:

- the magnitude of force at point A is 79.1033 lb

- since FA < FA_max; Ladder WILL NOT slip

Explanation:

Given that;

∑'MA = 0

⇒ NB [Lsin∅] - W[L/2.cos∅] = 0

NB = W / 2tan∅ -------let this be equation 1

∑Fx = 0

⇒ FA - NB = 0

FA = NB

therefore from equation 1

FA = NB = W / 2tan∅

we substitute in our values

FA = NB = 76 / 2tan(60°) = 21.9393 lb

Now ∑Fy = 0

NA - W = 0

NA = W = 76 lb

Net force at A will be

FA' = √( NA² + FA²)

= √( (W)² + (W / 2tan∅)²)

we substitute in our values

FA' = √( (76)² + (21.9393)²)

= √( 5776 + 481.3328)

= √ 6257.3328

FA' = 79.1033 lb

Therefore the magnitude of force at point A is 79.1033 lb

Now maximum possible frictional force at A

FA_max = μ × NA

so, FA_max = 0.4 × 76

FA_max = 30.4 lb

So by comparing, we can easily see that the actual friction force required for keeping the the ladder stationary i.e (FA) is less than the maximum possible friction available at point A.

Therefore since FA < FA_max; Ladder WILL NOT slip

5 0

3 years ago

Two children, Ferdinand and Isabella, are playing with a water hose on a sunny summer day. Isabella is holding the hose in her h

mojhsa [17]

Answer:

Isabella will not be able to spray Ferdinand.

Explanation:

We'll begin by calculating the time taken for the water to get to the ground from the hose held at 1 m above the ground. This can be obtained as follow:

Height (h) = 1 m

Acceleration due to gravity (g) = 9.8 m/s²

Time (t) =.?

h = ½gt²

1 = ½ × 9.8 × t²

1 = 4.9 × t²

Divide both side by 4.9

t² = 1/4.9

Take the square root of both side

t = √(1/4.9)

t = 0.45 s

Next, we shall determine the horizontal distance travelled by the water. This can be obtained as follow:

Horizontal velocity (u) = 3.5 m/s

Time (t) = 0.45 s

Horizontal distance (s) =?

s = ut

s = 3.5 × 0.45

s = 1.58 m

Finally, we shall compare the distance travelled by the water and the position to which Ferdinand is located to see if they are the same or not. This is illustrated below:

Ferdinand's position = 10 m

Distance travelled by the water = 1.58 m

From the above, we can see that the position of the water (i.e 1.58 m) and that of Ferdinand (i.e 10 m) are not the same. Thus, Isabella will not be able to spray Ferdinand.

8 0

3 years ago