Answer:
<em>The best explanation is that the first person is grounded to the earth, and his/her body either draws up negative charges from the earth, or tend to conducts negative charges to the earth, depending on the charge on the balloon.</em>
Explanation:
The earth is an infinite store for charges. In the first case where the second person brings a negatively charged balloon towards the first person, the negative charges on the balloon induces the first person's body to tend to attract the negative charges on the balloon through the first person's body to the positive charges within the earth. In the second case when again a positively charged balloon is brought near the first person's hair, the positive charges on the balloon induce the first person's body into drawing up negative charges from within the earth. This charges, and their opposite induced charges, create an attractive force between the hair strands and the balloons.
The mass of fuel the engine burn each second to produce a thrust of 7.66×10⁵ N is 2.5×10² kg/s.
<h3 /><h3>What is mass?</h3>
Mass can be defined as the quantity of matter contained in a body. The S.I unit of mass is kilogram(kg)
To calculate the mass the engine burns each seconds, we use the formula below.
Formual:
- M = T/v............. Equation
Where:
- M = Mass per seconds of the rocket
- T = Thrust
- v = Velocity
From the question,
Given:
- T = 7.66×10⁵ N
- v = 3.05×10³ m/s
Substitute these values into equation 1
- M = (7.66×10⁵)/(3.05×10³)
- M = 2.5×10² kg/s
Hence, the mass of fuel burned in each second is 2.5×10² kg/s.
Learn more about mass here: brainly.com/question/25121535
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Answer is B- 200 m
Given:
m (mass of the car) = 2000 Kg
F = -2000 N
u(initial velocity)= 20 m/s.
v(final velocity)= 0.
Now we know that
<u>F= ma</u>
Where F is the force exerted on the object
m is the mass of the object
a is the acceleration of the object
Substituting the given values
-2000 = 2000 × a
a = -1 m/s∧2
Consider the equation
<u>v=u +at</u>
where v is the initial velocity
u is the initial velocity
a is the acceleration
t is the time
0= 20 -t
t=20 secs
s = ut +1/2(at∧2)
where s is the displacement of the object
u is the initial velocity
t is the time
v is the final velocity
a is the acceleration
s= 20 ×20 +(-1×20×20)/2
<u>s= 200 m</u>
We can solve the problem by using Newton's second law of motion:

where
F is the net force applied to the object
m is the object's mass
a is the acceleration of the object
In this problem, the force applied to the car is F=1050 N, while the mass of the car is m=760 kg. Therefore, we can rearrange the equation and put these numbers in, in order to find the acceleration of the car:

The equation also tells us that the acceleration and the force have same directions: therefore, since the force exerted on the car is horizontal, the correct answer is
<span>
B) 1.4 m/s2 horizontally.</span>