Answer:
I = 2 kgm^2
Explanation:
In order to calculate the moment of inertia of the door, about the hinges, you use the following formula:
(1)
I: moment of inertia of the door
α: angular acceleration of the door = 2.00 rad/s^2
τ: torque exerted on the door
You can calculate the torque by using the information about the Force exerted on the door, and the distance to the hinges. You use the following formula:
(2)
F: force = 5.00 N
d: distance to the hinges = 0.800 m
You replace the equation (2) into the equation (1), and you solve for α:

Finally, you replace the values of all parameters in the previous equation for I:

The moment of inertia of the door around the hinges is 2 kgm^2
A simple electromagnet consisting of a coil of wire wrapped around an iron core. <u><em>A core of ferromagnetic material like iron serves to increase the magnetic field created.</em></u> The strength of magnetic field generated is proportional to the amount of current through the winding.
your answer is b :)
I LOVE YOUR PROFILE PICTURE!!!
For q3 to be in equilibrium the total force acting on it has to be zero.
Let's say that total distance traveled by car is L (this is just for the convenience).
We can set up a system of equations to find an answer. Let's say that from q1 to q3 the distance is r_1 and from q3 to q2 the distance is r_2, we know that this distance has to be equal to:

The second equation is going to the total force acting on the charge q3:

k_c is the Coulomb's constant. Since left-hand side is zero we just divide whole equation with k_c to get rid of it:

Let's solve this for r_1^2:

Now we have a quadratic equation with following parameter:

We know that two solutions are:

We need a positive solution. When we plug in all the numbers we get:
Work = (weight) x (distance)
Work = (50 lb) x (1 kg / 2.20462 lb) x (9.81 newton/kg)
x (4 feet) x (1 meter / 3.28084 feet)
= (50 x 9.81 x 4) / (2.20462 x 3.28084) newton-meter
= 271.3 joules .
We don't need to know how long the lift took, unless we
want to know how much power he was able to deliver.
Power = (work) / (time)
= (271.3 joule) / (5 sec) = 54.3 watts .
________________________________________
The easy way:
Work = (weight) x (distance)
= (50 pounds) x (4 feet) = 200 foot-pounds
Look up (online) how many joules there are in 1 foot-pound.
There are 1.356 joules in 1 foot-pound.
So 200 foot-pounds = (200 x 1.356) = 271.2 joules.
That's the easy way.
Answer:
70 kg is the mass of the object
Explanation:
This question can be solved with this simple formula:
Weight force = mass . gravity
686 N = mass . 9.8 m/s²
686 N / 9.8 m/s² = mass → 70 kg
Note → 1N = 1 kg . m / s²