Answer: B
Explanation: The motion sensor will measure the speed (velocity) of the car. Since the mass of the car has been measured, we can use formulas to calculate the average force.
Average net force = mass × acceleration
The mass of the toy car is measured first and noted
To calculate the velocity,
the car starts from rest since the velocity is associated with the distance and time after 5s.
Acceleration = velocity/time
With that the acceleration can be found.
acceleration is defined as change in velocity per unit time.
Then,
Force = mass × acceleration
Option B is the best answer
Answer:
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No; the sample could not be aluminum;
since the density of aluminum, " 2.7 g/cm³ " , is NOT close enough to the density of the sample, " 3.04 g/cm³ " .
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Explanation:
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Density is expressed as "mass per unit volume" ;
in which:
"mass, "m", is expressed in units of "g" (grams); and:
"Volume, "V", is expressed in units of "cm³ " (such as in this problem); or in units of "mL" ;
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{Note the exact conversion: " 1 cm³ = 1 mL " .}.
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The formula for density: D = m/V ;
Given: The density of aluminum is: 2.7 g/cm³.
Given: A sample has a mass of 52.0 g ; and Volume of 17.1 cm³ ; could it be aluminum?
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Let us divide the mass of the sample by the volume of the sample;
by using the formula:
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D = m / V ;
and see if the value is at, or very close to "2.7 g/cm³ ".
If it is, then it could be aluminum.
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The density for the sample:
D = (52.0 / 17.1) g/cm³ = 3.0409356725146199 g/cm³ ;
→round to "3 significant figures" ;
= 3.04 g/cm³ .
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No; the sample could not be aluminum; since the density of aluminum,
"2.7 g/cm³ " is NOT close enough to the density of the sample,
"3.04 g/cm³ " .
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Answer:
330 m/s
Explanation:
The sound wave has to travel TO the cliff AND back = 2 * 49.5 = 99 m
magnitude of velocity = distance / time = 99m / .3 s = 330 m/s
Answer:
v = 40 [m/s].
Explanation:
Linear momentum is defined as the product of mass by Velocity. In this way, by means of the following equation, we can calculate the momentum.

where:
m = mass [kg]
v = velocity [m/s]
![P =20*10\\P =200 [kg*m/s]](https://tex.z-dn.net/?f=P%20%3D20%2A10%5C%5CP%20%3D200%20%5Bkg%2Am%2Fs%5D)
Since all momentum is transferred, we can say that this momentum is equal for the mass of 5 [kg]. In this way, we can determine the speed after the impact.
![v = P/m\\v = 200/5\\v = 40 [m/s]](https://tex.z-dn.net/?f=v%20%3D%20P%2Fm%5C%5Cv%20%3D%20200%2F5%5C%5Cv%20%3D%2040%20%5Bm%2Fs%5D)
Answer:
The potential energy of the rock = 10.5 kN
Explanation:
Mass of rock = 25 kg
Acceleration due to gravity = 10 m/s²
Height = 42 m
Potential energy, PE = mgh, where m is the mass, g is acceleration due to gravity and h is the height.
PE = 25 x 10 x 42 = 10500 N = 10.5 kN
The potential energy of the rock = 10.5 kN