Answer:
635 years old
Explanation:
The light reaching the earth from the sun will travel at a speed called the speed of light, and this has a universal value of 3 × 10⁸ m/s. Bearing this in mind, let us calculate the age of the light reaching the Earth from the sun:
Distance of star from Earth = 6.1 × 10⁸m
Speed of light = 3 × 10⁸ m/s
We have distance and speed, let us calculate the time of travel of the light from the star to the earth.
Distance = speed × time
6.1 × 10⁸ = 3 × 10⁸ × time
In order to do the division above, we will divide the whole numbers normally, then we will apply the law of indices to the power that says:
Xᵃ ÷ Xᵇ = X⁽ᵃ⁻ᵇ⁾
Next, we are told that there are 3.2 × 10⁷ seconds in a year.
∴ The number of years travelled by the light from the star:
please note that:
2.03 × 10¹⁰ = 20300000000
3.2 × 10⁷ = 32000000
The closest answer in the option is 635 years, and we are short of this by some points due probably to approximations in the calculation.
Answer:
A
Explanation:
all the work is in the attached file :D
Answer:
The maximum static frictional force is 40N.
Explanation:
When an object of mass M is on a surface with a coefficient of static friction μ, there is a minimum force that you need to apply to the object in order to "break" the coefficient of static friction and be able to move the object (Called the threshold of motion, once the object is moving we have a coefficient of kinetic friction, which is smaller than the one for static friction).
This coefficient defines the maximum static friction force that we can have.
So if we apply a small force and we start to increase it, the static frictional force will be equal to our force until it reaches its maximum, and then we can move the object and now we will have frictional force.
In this case, we know that we apply a force of 40N and the object just starts to move.
Then we can assume that we are just at the point of transition between static frictional force and kinetic frictional force (the threshold of motion), thus, 40 N is the maximum of the static frictional force.
Answer:
F is non-conservative.
If F were conservative no work would be done in moving back to the original point. F dot S = W if the net distance is zero the work done is zero for a conservative force
You fallow the steps to figure out the complete answer of the question.
