1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Pavlova-9 [17]
3 years ago
11

A 10g bullet traveling at 450m/s strikes a 7.0kg , 1.1m--wide door at the edge opposite the hinge. the bullet embeds itself in t

he door, causing the door to swing open. what is the angular velocity of the door just after impact?
Physics
1 answer:
Lesechka [4]3 years ago
5 0

Using momentum balance, we can say that the momentum before the strike and after the strike are equal. Therefore:

m1 v1 + m2 v2 = m’ v’

However the door is not moving before the strike therefore v2 = 0:

0.010 kg * 450 m/s + 0 = (7.010 kg) v’

<span>v’ = 0.64 m/s </span>

You might be interested in
Trace the path of a ray emitted from the tip of the object toward the focal point of the mirror and then the reflected ray that
Crazy boy [7]

Answer: find the attached files for the answer

Explanation:

The reflected ray appears to have originated from the focal point. We should actually draw a vector from the focal point through the point where the incident ray hits the mirror but we shorten the vector so that its starting point is on the mirror, without changing its angle.

Please find the attached files for the solution

5 0
3 years ago
A penny rides on top of a piston as it undergoes vertical simple harmonic motion with an amplitude of 4.0cm. If the frequency is
aniked [119]

1) At the moment of being at the top, the piston will not only tend to push the penny up but will also descend at a faster rate at which the penny can reach in 'free fall', in that short distance. Therefore, at the highest point, the penny will lose contact with the piston. Therefore the correct answer is C.

2) To solve this problem we will apply the equations related to the simple harmonic movement, hence we have that the acceleration can be defined as

a = -\omega^2 A

Where,

a = Acceleration

A = Amplitude

\omega= Angular velocity

From a reference system in which the downward acceleration is negative due to the force of gravity we will have to

a = -g

-\omega^2 A = -g

\omega = \sqrt{\frac{g}{A}}

From the definition of frequency and angular velocity we have to

\omega = 2\pi f

f = \frac{1}{2\pi} \sqrt{\frac{g}{A}}

f = \frac{1}{2\pi} \sqrt{\frac{9.8}{4*10^{-2}}}

f = 2.5Hz

Therefore the maximum frequency for which the penny just barely remains in place for the full cycle is 2.5Hz

6 0
3 years ago
Nick parks his car at Target and walks 150 ft. north to get to the store. On his way back to the car, he walks 50 ft. before pau
mr Goodwill [35]
75 steps is what he’s missing
7 0
3 years ago
Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. The scale reads 830 N for the first 3.8 s after the eleva
Delicious77 [7]

Answer:

v= 4.0 m/s

Explanation:

  • When standing on the bathroom scale within the moving elevator, there are two forces acting on Henry's mass: Normal force and gravity.
  • Gravity is always downward, and normal force is perpendicular to the surface on which the mass is located (the bathroom scale), in upward direction.
  • Normal force, can adopt any value needed to match the acceleration of the mass, according to Newton's 2nd Law.
  • Gravity (which we call weight near the Earth's surface) can be  calculated as follows:

       F_{g} = m*g = 95 kg * 9.8 m/s2 = 930 N (1)

  • According to Newton's 2nd Law, it must be met the following condition:

       F_{net} = F_{g} -F_{n} = m*a\\  F_{net} = 930 N - 830 N = 100 N = 95 Kg * a

  • As the gravity is larger than normal force, this means that the acceleration is downward, so, we choose this direction as the positive.
  • Solving for a, we get:

       a =\frac{F_{net} }{m} =\frac{100 N}{95 kg} =  1.05 m/s2

  • We can find the speed after the first 3.8 s (assuming a is constant), applying the definition of acceleration as the rate of change of velocity:

        v_{f} = a* t = 1.05 m/s * 3.8 m/s = 4.0 m/s

  • Now, if during the next 3.8 s, normal force is 930 N (same as the weight), this means that both forces are equal each other, so net force is 0.
  • According to Newton's 2nd Law, if net force is 0, the object  is either or at rest, or moving at a constant speed.
  • As the elevator  was moving, the only choice is that it is moving at  a constant speed, the same that it had when the scale was read for the first time, i.e., 4 m/s downward.
3 0
3 years ago
Why it is important to have exact standards of measurement
Tamiku [17]

Answer:

reference against doubt

Explanation:

exact standards of measurement are a reference point for situations in doubt , a line against which to test and observe.

6 0
3 years ago
Other questions:
  • Which is a better conductor, metal or non metal
    11·1 answer
  • Which statement is accurate with regard to migration to metropolitan areas from 1995 to 2000?.
    7·1 answer
  • Jonathan answered 28 out of 35 questions correctly on his chemistry test. What is his percent score?
    15·1 answer
  • Why does the gravitational force between earth and moon predominate over electrical forces?
    10·1 answer
  • Two blocks, one of mass 5 kg and the other of mass 2 kg, are attached to opposite ends of a light string and hung vertically fro
    6·1 answer
  • A grasshopper jumps and accelerates at 4.5 m/s2. If its legs exert a force of 0.062 N during the jump, what is the mass of the g
    15·1 answer
  • An electron is pushed into an electric field where it acquires a 1-V electrical potential. Suppose instead that two electrons ar
    12·1 answer
  • What happens to the particles in a substance when temperature rises
    6·1 answer
  • Red Riding Hood sat down to rest and placed her 1.20-kg basket of goodies beside her. A wolf came along, spotted the basket, and
    7·1 answer
  • What are the factor affecting the moment of force
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!