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3 years ago

What is the farthest distance parallaxes can be used to measure star distances from Earth?

1 answer:

8 0

Using current technology, useful parallax measurements can only be found for stars up to about 340 light years (100 parsecs) away.

You might be interested in

Name two ways that friction is harmful and two ways that friction is helpful to you when riding a bicycle

lawyer [7]

<u>Harmful</u><u />

-causes heat; if it's not used correctly, it can cause injury
-when falling, the friction between your knee/leg and the ground can cause scrapes
<u>
</u><u>Helpful</u><u />

-helps stop the bike, the brakes rub against the tire which slows it down to a stop
-it can also help move the bike; the chains rub against tires which accelerate the bike

6 0

3 years ago

When NASA was communicating with astronauts on the Moon, the time from sending on the Earth to receiving on the moon was 1.33 s.

frez [133]

To solve this problem it is necessary to apply the concepts related to the kinematic equations of movement description, which determine the velocity, such as the displacement of a particle as a function of time, that is to say

$v = \frac{x}{t}\rightarrow x = v*t$

Where,

x = Displacement

v = Velocity

t = Time

Our values are given as,

$v=3*10^8m/s$

$t = 1.33 s$

Replacing we have that,

$x=v*t$

$x=(3*10^8)(1.33)$

$x = 399'000.000m$

Therefore the distance from Earth to the Moon is 399.000 km

5 0

3 years ago

A supply bag is dropped from a rescue plane. After the bag falls for 3.2 seconds , what is the velocity of the bag?

loris [4]

Answer: -31.36 m/s

Explanation:

This is a problem of motion in one direction (specifically vertical motion), and the equation that best fulfills this approach is:

$V_{f}=V_{o}+a.t$ (1)

Where:

$V_{f}$ is the final velocity of the supply bag

$V_{o}=0$ is the initial velocity of the supply bag (we know it is zero because we are told it was "dropped", this means it goes to ground in free fall)

$a=g=-9.8m/s^{2}$ is the acceleration due gravity (the negtive sign indicates the gravity is downwards, in the direction of the center of the Earth)

$t=3.2s$ is the time

Knowing this, let's solve (1):

$V_{f}=0+(-9.8m/s^{2})(3.2s)$ (2)

Finally:

$V_{f}=-31.36m/s$ Note the negative sign is because the direction of the bag is downwards as well.

8 0

3 years ago

Two 1-kg objects, C and D, increase in temperature by the same amount, but the

Ede4ka [16]

The object D is made up of material Lead. The correct option is D.

<h3>What is specific heat?</h3>

The specific heat is the amount of heat required to change the temperature by 1°C. It is denoted by C.

Two 1-kg objects, C and D, increase in temperature by the same amount, but the thermal energy transfer of object C is greater than the thermal energy transfer of object D. The object C has a specific heat of 235 J/kg-K.

Q = m C ΔT

Qc > Qd

The energy transfer is proportional to specific heat.

Specific heat of D must be less. The possible material with specific heat less than the given value is for Lead material.

Thus, the correct option is D.

Learn more about specific heat,

brainly.com/question/11297584

#SPJ1

4 0

1 year ago

If the sum of the external forces on an object is zero, then the sum of the external torques on it

Zarrin [17]

Answer:

True.

Explanation:

If the sum of the external forces on an object is zero, then the sum of the external torques on it must also be zero.

The net external force and the net external torque acting on the object have to be zero for an object to be in mechanical equilibrium.

Hence, the given statement is true.

5 0

3 years ago