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3 years ago

A 1.5-kilogram cart initially moves at 2.0 meters

1 answer:

7 0

   Acceleration = (change in speed) / (time for the change)

Change in speed = (speed at the end) minus (speed at the beginning.

The cart's acceleration is

   (0 - 2 m/s) / (0.3 sec)

   = ( -2 / 0.3 ) (m/s²) = -(6 and 2/3) m/s² .

Newton's second law of motion says

   Force = (mass) x (acceleration) .

For this cart: Force = (1.5 kg) x ( - 6-2/3 m/s²)

   = ( - 1.5 x 20/3 ) (kg-m/s²)

   = - 10 newtons .

The force is negative because it acts opposite to the direction
in which the cart is moving, it causes a negative acceleration,
and it eventually stops the cart.

You might be interested in

Refer to the first diagram. What is the weight of the person hanging on the end of the seesaw in Newtons?

irina1246 [14]

Due to equilibrium of moments:

1) The weight of the person hanging on the left is 250 N

2) The 400 N person is 3 m from the fulcrum

3) The weight of the board is 200 N

Explanation:

To solve the problem, we use the principle of equilibrium of moments.

In fact, for the seesaw to be in equilibrium, the total clockwise moment must be equal to the total anticlockwise moment.

The moment of a force is defined as:

$M=Fd$

where

F is the magnitude of the force

d is the perpendicular distance of the force from the fulcrum

In the first diagram:

- The clockwise moment is due to the person on the right is

$M_c = W_2 d_2$

where $W_2 = 500 N$ is the weight of the person and $d_2 = 2 m$ is its distance from the fulcrum

- The anticlockwise moment due to the person hanging on the left is

$M_a = W_1 d_1$

where $W_1$ is his weight and $d_1 = 4 m$ is the distance from the fulcrum

Since the seesaw is in equilibrium,

$M_c = M_a$

So we can find the weight of the person on the left:

$W_1 d_1 = W_2 d_2\\W_1 = \frac{W_2 d_2}{d_1}=\frac{(500)(2)}{4}=250 N$

Again, for the seesaw to be in equilibrium, the total clockwise moment must be equal to the total anticlockwise moment.

- The clockwise moment due to the person on the right is

$M_c = W_2 d_2$

where $W_2 = 400 N$ is the weight of the person and $d_2$ is its distance from the fulcrum

- The anticlockwise moment due to the person on the left is

$M_a = W_1 d_1$

where $W_1 = 300 N$ is his weight and $d_1 = 4 m$ is the distance from the fulcrum.

Since the seesaw is in equilibrium,

$M_c = M_a$

So we can find the distance of the person on the right:

$W_1 d_1 = W_2 d_2\\d_2 = \frac{W_1 d_1}{W_2}=\frac{(300)(4)}{400}=3 m$

As before, for the seesaw to be in equilibrium, the total clockwise moment must be equal to the total anticlockwise moment.

- The clockwise moment around the fulcrum this time is due to the weight of the seesaw:

$M_c = W_2 d_2$

where $W_2$ is the weight of the seesaw and $d_2 = 3 m$ is the distance of its centre of mass from the fulcrum

- The anticlockwise moment due to the person on the left is

$M_a = W_1 d_1$

where $W_1 = 600 N$ is his weight and $d_1 = 1 m$ is the distance from the fulcrum

Since the seesaw is in equilibrium,

$M_c = M_a$

So we can find the weight of the seesaw:

$W_1 d_1 = W_2 d_2\\W_2 =\frac{W_1 d_1}{d_2}= \frac{(600)(1)}{3}=200 N$

#LearnwithBrainly

8 0

3 years ago

A current of 3.6-A flows through a conductor. Calculate how much charge passed through and cross-section of the conductor in 25s

Anastaziya [24]

Answer:

90 C

Explanation:

Electric current: This can be defined as the rate of flow of electric charge in a circuit. This can be expressed mathematically as,

I = dQ/dt

dQ = Idt

∫dQ = ∫Idt

Q = It................................ Equation 1

Where Q = amount of charge, I = current, t = time.

Given: I = 3.6 A, t = 25 s.

Substituting into equation 1,

Q = 3.6(25)

Q = 90 C.

Hence the amount of charge passing through the cross section of the conductor = 90 C

6 0

3 years ago

Would u rather/ have a penny that duplicates its self every day or win 1 million dollars once

arlik [135]

Answer:

1 million dollars once

Explanation:

Well, both would be nice. In total, you will get more from the million dollars because it takes over 2,739 years to get 1 million dollars worth of pennies.(if you get 1 a day that is)

8 0

3 years ago

What do we call the principal SI units that are used to derive all other SI units? Question 3 options:

Angelina_Jolie [31]

Answer: Base units

The principal SI units that are used to derive all other SI units are called base units. The base units are the units of fundamental quantities e.g. M L T that is Mass, Length, and Time. All other physical quantities can be written in the fundamental dimension forms. The physical quantities are not measured directly but are build up from the building blocks that are the fundamental quantities which have base units.

5 0

3 years ago

A penny is dropped from the top of a tower. It hits the ground below after 2.5 s. How tall was the tower?

pychu [463]

Answer:

C. 30.6m

Explanation:

To find the height of the tower, we are to use Newtons law of motion to solve this problem. Since the penny is falling from the top of the tower, it is acted by the acceleration due to gravity. The formula to be used is:

$H=ut+\frac{1}{2}gt^2$

Where H is the height of the tower, t is the time taken to hit the ground, u is the initial velocity and g is the acceleration due to gravity.

Given that, t = 2.5 s, g =9.8 m/s², u = 0 m/s (at the top of tower)

$H=ut+\frac{1}{2}gt^2\\\\H=0(2.5)+ \frac{1}{2}(9.8)(2.5)^2\\\\H=30.6\ m$

3 0

3 years ago