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
pentagon [3]
3 years ago
14

Two blocks, joined by a string, have masses of 6.0 and 9.0 kg. They rest on a frictionless, horizontal surface. A second string,

attached only to the 6.0-kg block, has horizontal force = 45 N applied to it. Both blocks accelerate. Find the tension in the string between the blocks.
Physics
1 answer:
Lynna [10]3 years ago
4 0

Answer:

T= 27 N

Explanation:

Assuming that the string joining both masses is massless  and inextensible, both masses accelerate at the same rate.

So, we can treat to both masses as a single system, and apply Newton's 2nd Law to both masses.

In this way, we can get the value of the acceleration without taking into account the tension in the string, as it is an internal force (actually a action-reaction pair).

Newton's 2nd law is a vector equation, so we can decompose the forces along perpendicular axis in order to convert it in two algebraic equations.

We can choose one axis as parallel to the horizontal surface (we call it x-axis, being the positive direction the one of  the movement of the blocks due to the horizontal force applied to the 6.0 kg block), and the other, perpendicular to it, so it is vertical (we call y-axis, being the upward direction the positive one).

Taking into account the forces acting  on both masses, we can write both equations as follows:

Fy = N- (m₁+m₂)*g = 0 (as there is no movement in the vertical direction)

Fx = Fh = (m₁ + m₂) * a ⇒ 45 N = 15.0 kg * a

⇒ a = 45 N / 15.0 kg = 3 m/s²

Now, in order to get the value of the tension T, we can choose as our system, to any mass, and apply Newton's 2nd Law again.

If we choose to the mass of 6.0 kg, in the horizontal direction, there are two forces acting on it, in opposite directions: the  horizontal applied force of 45 N, and the tension in the string that join both masses.

The difference of both forces, must be equal to the mass (of this block only) times the acceleration, as follows:

F- T = m₂* a ⇒ 45 N - T = 6.0 kg * 3 m/s²

⇒ T = 45 N -18 N = 27 N

We could have arrived to the same result taking the 9.0 Kg as our system, as the only force acting in the horizontal direction is just the tension in the string that we are trying to find out, as follows:

F = m₁*a = 9.0 kg* 3 m/s² = 27 N

You might be interested in
Joe rides his bicycle in a straight line for 2 hour with an average velocity of 13 km/h south, how far has he ridden?
dmitriy555 [2]

Answer:

ans is 3.125 km

i hope this is correct

8 0
3 years ago
Over a period of operation, the useful work output of the fluorescent bulb was
Nadya [2.5K]

Answer:

199.0521 Will be the answer

5 0
3 years ago
A dumbell has a mass of 95 kg. What force must be applied to accelerate it upward at 2.2 m/s2?
Sveta_85 [38]
A :-) F = ma
Given - m = 95 kg
a = 2.2 m/s^2
Solution -
F = ma
F = 95 x 2.2
F = 209

.:. The force is 209 N
5 0
3 years ago
A 16-slug mass is raised by 10 ft. the PE of the mass increased by?
Eva8 [605]

Answer:

<em>The PE of the mass increased by 6,972.95 J</em>

Explanation:

<u>Gravitational Potential Energy</u>

It's the energy stored in an object because of its vertical position or height in a gravitational field.

It can be calculated with the equation:

U=m.g.h

Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or 9.8 m/s^2.

We are given the mass of m=16 slug raised by a height h=10 ft. Both units will be converted to SI standard:

1 slug = 14.59 Kg, thus

16 slug = 16*14.59 Kg=233.44 Kg

1 ft = 0.3048 m, thus:

10 ft = 10*0.3048 m = 3.048 m

Thus, the PE of the mass increased by:

U = 233.44 * 9.8 * 3.048 = 6,972.95 J

the PE of the mass increased by 6,972.95 J

4 0
3 years ago
How do constructive and destructive forces change earth
Virty [35]
The surface of the earth changes. Some changes are due to slow processes, such as erosion and weathering, and some changes are due to rapid processes, such as landslides, volcanic eruptions, and earthquakes.
3 0
3 years ago
Other questions:
  • Which of the following statements about energy is true? I. Kinetic energy cannot be transformed into another type of energy. II.
    8·2 answers
  • A rock is rolling down a hill. At position 1, its velocity is 2.0 m/s. Twelve seconds later, as it passes position 2, its veloci
    7·2 answers
  • Why must one use a reference point to determine whether or not an object is in motion
    14·1 answer
  • A jet airplane lands with a speed of 120 mph. It has 1800 ft of runway after touch- down to reduce its speed to 30 mph. Compute
    15·1 answer
  • If F(theta)=tan theta=3, find F(theta+pi)
    7·1 answer
  • A car starts from rest and accelerates uniformly over a time of 10.21 seconds for a distance of 210 m. Determine the acceleratio
    10·1 answer
  • What is the net force on a bathroom scale when a 150-pound person stands on it
    12·1 answer
  • A nonconducting sphere of radius r0 carries a total charge q distributed uniformly throughout its volume
    11·1 answer
  • When a car maintains a velocity of exactly 65 mph, what is it's acceleration​
    12·2 answers
  • At which points on the roller coaster is the car not moving?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!