5
if zero falls between two significant numbers it becomes significant.
This problem can be solved using a kinematic equation. For this case, the following equation is useful:
v_final = v_initial + at
where,
v_final = final velocity of the nail
v_initial = initial velocity of the nail
a = acceleration due to gravity = 9.8 m/s^2
t = time
First, we determine the time it takes for the nail to hit the ground. We know that the initial velocity is 0 m/s since the nail was only dropped. It has a final velocity of 26 m/s. We substitute these values to the equation and solve for t:
26 = 0 + 9.8*t
t = 26/9.8 = 2.6531 s
The problem asks the velocity of the nail at t = 1 second. We then subtract 1 second from the total time 2.6531 with v_final as unknown.
v_final = 0 + 9.8(2.6531-1) = 16.2004 m/s.
Thus, the nail was traveling at a speed of 16. 2004 m/s, 1 second before it hit the ground.
<u>Answer: The model is described by :</u>
The strength of the field increases as you get closer to Earth, as shown by the smaller spaces between the circles.
Explanation :
According to universal gravitational law, the force acting in the universe between two objects is given by :

It is clear that the gravitational force depends directly on the product of masses and inversely on the square of the distance between them.
The given image shows a model of the gravitational field around Earth. The arrows in the image show the direction of the force. Gravitational field depends on the position of objects.
As we move closer to the earth, the force increases and hence the field increase.
So, the correct option is (D) " The strength of the field increases as you get closer to Earth, as shown by the smaller spaces between the circles ".
Normal reaction force on the block while it is at rest on the inclined plane is given as

here we know that
m = 46 kg

now we will have

now the limiting friction or maximum value of static friction on the block will be given as


Above value is the maximum value of force at which block will not slide
Now the weight of the block which is parallel to inclined plane is given as

here we know that

Now since the weight of the block here is less than the value of limiting friction force and also the block is at rest then the frictional force on the block is static friction and it will just counter balance the weight of the block along the inclined plane.
So here <u>friction force on the given block will be same as its component on weight which is 218.55 N</u>
Answer:
Ke=electron kinetic energy=
Explanation:
The electron has a mass of 
The speed of light in a vacuum is a universal constant with the value 299 792 458 m / s (186 282,397 miles / s), although it is usually close to 
Kinetic energy (K) is the energy associated with bodies that are in motion, depends on the mass and speed of the body and is calculated using the formula:
Equation(1)
K=kinetic energy (J)
m =mass of the body (kg)
v= speed of the body
for this problem We replace in the equation (1)
= electron mass
=Half the speed of light
=electron speed
We replace in the equation (1) :




The energy kinetic of the electron is 