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3 years ago

The SI system uses three base units. Question 6 options: True False

Physics

1 answer:

GalinKa [24]3 years ago

6 0

Answer:

The answer is false

Explanation:

Though the mostly used SI unit of measurement or the most popular units are the

Length,

Time and

Mass

i.e meter (m), seconds (s), kilogram (kg)

Aside all the above stated units for measurements there are other four basic units which are itemized bellow.

they are

1. Amount of substance - mole (mole)

2. Electric current - ampere (A)

3. Temperature - kelvin (K)

4. Luminous intensity - candela (cd)

You might be interested in

Two upwards forces act: one of 34N which is 3.5m to the left of the axle, the other is 25N and is 2.6m to the right of the axle.

KiRa [710]

Answer:

See explanation below

Explanation:

In this case, you want to know if you put an object between these forces, which direction would go.

To know this, we need to calculate the moment of an object, which is defined as the product of a force and it's distance. In other words:

M = F * d (1)

And, in order to reach equilibrium the force will exert a direction in clockwise or anticlosewise, and these moments, should be even:

anticlockwise moment = clockwise moment.

The clockwise would be the forces to the right, and anticlock would the only force to the left of the axle.

Clockwise moment = (10 * 0.8) + (25 * 2.6) = 73 Ns

Anticlockwise moment = 34 * 3.5 = 119 Ns.

As we can see, the moment in the anticlockwise is higher than the actual clockwise moment, therefore, we can assume that the object will move anticlockwise, or simply move to the left.

Hope this helps

5 0

3 years ago

Each of the gears a and b has a mass of 675 g and has a radius of gyration of 40 mm, while gear c has a mass of 3. 6 kg and a ra

navik [9.2K]

9.87 seconds

The time required for this system to come to rest is equal to 9.87 seconds.

We have the following data:

Mass of gear A = 675 g to kg = 0.675 kg.

Radius of gear A = 40 mm to m = 0.04 m.

Mass of gear C = 3.6 kg.

Radius of gear C = 100 mm to m = 0.1 m.

How can I calculate the time needed?

We would need to figure out the moment of inertia for gears A and C in order to compute the time needed for this system to come to rest.

Mathematically, the following formula can be used to determine the moment of inertia for a gear:

I = mr²

Where:

m is the mass.

r is the radius.

We have, For gear A:

I = mr²

I = 0.675 × 0.04²

I = 0.675 × 0.0016

I = 1.08 × 10⁻³ kg·m².

We have, For gear C:

I = mr²

I = 3.6 × 0.1²

I = 3.6 × 0.01

I = 0.036 kg·m².

The initial angular velocity of gear C would therefore be converted as follows from rotations per minute (rpm) to radians per second (rad/s):

ωc₁ = 2000 × 2π/60

ωc₁ = 4000π/60

ωc₁ = 209.44 rad/s.

Also, the initial angular velocity of gears A and B is given by:

ωA₁ = ωB₁ = rc/rA × (ωc₁)

ωA₁ = ωB₁ = 0.15/0.06 × (209.44)

ωA₁ = ωB₁ = 2.5 × (209.44)

ωA₁ = ωB₁ = 523.60 rad/s.

Taking the moment about A, we have:

I_A·ωA₁ + rA∫F_{AC}dt - M(f)_A·t = 0

On Substituting the given parameters into the formula, we have;

(1.08 × 10⁻³)·(523.60) + 0.06∫F_{AC}dt - 0.15t = 0

0.15t - 0.06∫F_{AC}dt = 0.56549 ----->equation 1.

Similarly, the moment about B is given by:

0.15t - 0.06∫F_{BC}dt = 0.56549 ------>equation 2.

Note: Let x = ∫F_{BC}dt + ∫F_{AC}dt

Adding eqn. 1 & eqn. 2, we have:

0.3t - 0.06x = (0.56549) × 2

0.3t - 0.06x = 1.13098 ------>equation 3.

Taking the moment about A, we have:

Ic·ωc₁ - rC∫F_{AC}dt - rC∫F_{BC}dt - Mc(f)_A·t = 0

0.036(209.44) - 0.3t - 0.15(∫F_{BC}dt + ∫F_{AC}dt) = 0

0.3t + 0.15x = 7.5398 ------->equation 4.

Solving eqn. 3 and eqn. 4 simultaneously, we have:

x = 30.5 Ns.

Time, t = 9.87 seconds.

To learn more about moment of inertia visit:

brainly.com/question/15246709

#SPJ4

6 0

2 years ago

What Are the Advantages of SI unit<br><br>

jasenka [17]

Answer:

1)SI is coherent system of units

2) SI is rational system of units

7 0

2 years ago

I need to speak with zuka

Alex787 [66]

Answer:

DMs are not accessible anymore. I assume Zuka is a staff member? the only way to talk to a staff member anymore is to report something, but even then, the probably won't even look at what they're deleting :/

May I have brainliest please? :)

3 0

3 years ago

Which is not expecting acceleration?

Elena L [17]

A point on the outside of a spinning top whose rotational speed is constant.

Since the point at the top is at rest so it will not accelerate at all

A skydiver whose air resistance is equal to that of her weight.

Since weight is counter balanced by air resistance so net force on it is zero so acceleration will be zero

A car on the freeway experiencing a net force of -120 N.

Since net force is not zero so it will accelerate here

A submerged beach ball whose buoyant force is eight times the force of gravity on it.

Since buoyant force is more than the weight so it will not at rest and move upwards with some acceleration

A frictionless spinning merry go round.

Since spinning wheel accelerating due to centripetal force so it is non inertial frame

A falling rock.

Falling rock is accelerating due to gravity so it is again non inertial frame

A hot air balloon moving at 30 degrees east of north with no net force.

since hot air balloon is having no force on it so its acceleration is zero and its an inertial frame

A space shuttle whose boosters just ignited for takeoff.

Since space shuttle is accelerating due to boosters so it is non inertial frame

Here net force on it is due to two given forces

$F_1 = 4320 N$ towards right

$F_2 = 4380 N$ towards left

so here net force is given as

$F = F_2 - F_1$

$F = 4380 - 4320 = 60 N$

since force towards left is more so the direction will be towards left

so correct answer is 60 N towards left

4 0

3 years ago