Ask question

Ask question

All categories

3 years ago

8

An astronaut in space cannot use a conventional means, such as a scale or balance, to determine the mass of an object. But she d

oes have devices to measure distance and time accurately. She knows her own mass is 78.4 kg, but she is unsure of the mass of a large gas canister in the airless rocket. When this canister is approaching her at 3.50 m/s, she pushes against it, which slows it down to 1.20 m/s (but does not reverse it) and gives her a speed of 2.40 m/s. What is the mass of this canister

1 answer:

Flura [38]3 years ago

7 0

Answer:

81.81 kg

Explanation:

$m_1$ = Mass of person = 78.4 kg

$m_2$ = Mass of canister

$u_1$ = Initial velocity of person = 0

$u_2$ = Initial velocity of canister = 3.5 m/s

$v_1$ = Final velocity of person = 2.4 m/s

$v_2$ = Final velocity of canister = 1.2 m/s

The momentum balance in the system is given by

$m_1u_1+m_2u_2=m_1v_1+m_2v_2\\\Rightarrow 78.4\times 0+m_2\times 3.5=78.4\times 2.4+m_2\times 1.2\\\Rightarrow m_2=\dfrac{78.4\times 2.4}{3.5-1.2}\\\Rightarrow m_2=81.81\ \text{kg}$

Mass of the canister is 81.81 kg.

You might be interested in

A large truck with a mass of 3200 kg is pulling a trailer with a mass of 2400 kg. Both are accelerating at a rate of 0.45 . Dete

Gwar [14]

Given:

Mass of truck, m1 = 3200 kg

Mass of trailer, m2 = 2400 kg

acceleration = 0.45 m/s²

Let's determine the following:

(a) The tension force between the truck and the trailer.

To find the tension between the truck and the trailer, apply the formula:

$F_{\text{net}}=a(m_1+m_2)$

Where:

Fnet is the tension between the truck and the trailer

a is the acceleration = 0.45 m/s²

m1 is the mass if the truck = 3200 kg

m2 is the mass of trailer = 2400 kg

Hence, we have:

$\begin{gathered} F_{net}=0.45(3200+2400) \\ \\ F_{\text{net}}=0.45(5600) \\ \\ F_{\text{net}}=2520\text{ N} \end{gathered}$

Therefore, the tension between the truck and the trailer is 2520N

(b) The force with which the truck is pulling.

The tension between the truck and the trailer is equivalent to the force on the trailer.

thus, we have:

$\begin{gathered} T=m_2a \\ \\ T=2400\times0.45 \\ \\ T=1080\text{ N} \end{gathered}$

Therefore, the force with which the truck is pulling is 1080N.

ANSWER:

(a) 2520N

(b) 1080 N

8 0

2 years ago

A magnetic field is decreasing in strength. According to Lenz's law, what prediction can be made about the magnetic field it ind

lesya692 [45]

Answer:

Did you ever get the answer?

Explanation:

8 0

3 years ago

A 50n brick is suspended by a light string from a 30kg pulley which may be considered a solid disk with radius 2.0m. the brick i

igomit [66]

Brick is held at a position which is at height 2 m from the floor

Now it is released from rest and hit the floor after t = 4 s

Now the acceleration of the brick is given by

$y = v_i* t + 0.5 at^2$

$2 = 0 + 0.5 * a * 4^2$

$a = 0.25 m/s^2$

a)

Now in order to find the tension in the string

we can use Newton's law

$F_{net} = ma$

$mg - T = ma$

$50 - T = \frac{50}{9.8}*0.25$

$T = 48.72 N$

part b)

Now for the pulley

moment of inertia= $\frac{1}{2}mr^2$

m = 30 kg

R = 2 m

I = $\frac{1}{2}*30*2^2$

I = 60 kg m^2

Now the angular speed just before brick collide with the floor

$w = \frac{v}{r}[\tex]here we have[tex]v = v_i + a* t$

$v = 0 + 0.25 * 4$

v = 1 m/s

Now we will have

L = angular momentum = I w = $I*\frac{v}{R}$

L = 60 * $\frac{1}{2}$

L = 30 kg m^2/s

8 0

3 years ago

Incident rays parallel to the axis of a concave mirror reflect parallel to the axis.

coldgirl [10]

No they don't. Incident rays parallel to the axis of a concave mirror
reflect from the mirror's surface and converge at its focal point.

3 0

3 years ago

Salma is riding her bicycle. She rides 25.6 kilometers in 4 hours. What is her speed?

Musya8 [376]

Answer:

6.4 kilometers per hour

Explanation:

Just do the amount of distance she covers divided by how many hours she rides to get the answer. In this case, its 25.6 divided by 4 which equals 6.4

3 0

3 years ago