If the stone loses 10% of its speed in 10 s of grinding, what is the force with which the man presses the knife against the stone?

Answers

Answer 1

Answer: w1=200rpm*2pi/60=20.9rad/s

w2=200rpm-.10(200rpm)=180rpm

180rpm*2pi/60=18.8rad/s

a=(18.8-20.9)/10= -.21rad/s^2

I=1/2(28)(.15)^2
I=.315kg*m^2
Torque= -.21(.315)=.06615 N*m
Friction force= -.06615/.15=-.441 N
Normal force of man=.441/.2= 2.205 N
Final answer: -2.205 N

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A car travels at a steady speed of 10 m/s. What distance is covered in a minute?

Answers

Answer:

600

Explanation:

10*60=600

You multiply it by 60 because it is saying that it travels 1 mile per second and there are 60 seconds in one minute.

Which of these are considered an oxidizing mutagenic agent? x–rays benzopyrene gamma rays

Answers

X - rays are considered an oxidizing mutagenic agent. X-rays are high energy electrons that can cause damage when exposed under extreme conditions. The best technology that can block it is t using a lightweight type of metal foam. It can take in high energy collisions which also exhibits high forces. it does not only block x-rays but also, neutron radiation and gamma rays.

as you are leaving a building, the door opens outward. if the hinges on the door are on your right, what is the direction of the angular velocity of the door as you open it?

Answers

The correct answer for the question that is being presented above is this one: "B) down." As you are leaving a building, the door opens outward. if the hinges on the door are on your right, the angular velocity of thedoor as you open it us 'down.'

Here are the following choices:
A) up
B) down
C) to your left
D) to your right

Pressure and volume changes at a constant temperature can be calculated usinga. Boyle s law.
c. Kelvin s law.
b. Charles s law.
d. Dalton s law.

Answers

It can be calculated using Boyle's Law. A.

Charge q is 1 unit of distance away from the source charge S. Charge p is two times further away. The force exerted between S and q is _____ the force exerted between S and p. a. 1/2
b. 2 times
c. 1/4
d. 4 times

Answers

Answer : The correct option is, (d) 4 times

Solution :

According to the Coulomb's law, the electrostatic force of attraction or repulsion between two charges is directly proportional to the product of the charges and is inversely proportional to the square of the distance between the the charges.

Formula used :

$F=k_e(q_1q_2)/(r^2)$

where,

F = electrostatic force of attraction or repulsion

$k_e$ = Coulomb's constant

$q_1$ and $q_2$ are the charges

r = distance between two charges

First we have to calculate the force exerted between S and q when the distance between the charge is 1 unit and let us assumed that the charge be 'q'

$F_(sq)=k_e(qq)/(1^2)=k_e* q^2$ ..........(1)

Now we have to calculate the force exerted between S and p when the distance between the charge is 2 unit at the same charge.

$F_(sp)=k_e(qq)/(2^2)=k_e(q^2)/(4)$ ...........(2)

Equation equation 1 and 2, we get

$(F_(sq))/(F_(sp))=(1)/(4)$

$F_(sq)=4* F_(sp)$

Therefore, the force exerted between S and q is 4 times the force exerted between S and p.

I believe the answer is "4 times".

brad rides his bike 20 km . he covers the distance in 45 minutes (0.75 hours) what is his speed in kilometers per hours ? a. 44 km/hr b. 15 km/hr c. 9.0 km/hr d. 27 km/hr

Answers

D. 27 km/hr :) Just msg if you need any more help :)

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