Answer:
They will be 140 miles apart 8 hours after the first boy started the trip or 6 hours after the second boy started the trip.
Explanation:
x = the time that the first boy travels at 14 mph
x - 2 = the time the second boy travels at 14 mph
140 the distance between them
Since one travels north and the other east (their roads are perpendicular) the distance between them can be calculated using Pythagorean Theorem
(14*x)^2 + ((x-2)*14)^2 = 140^2
the solutions of the quadratic equation are
x1 = - 6 is not the solution since x > 0
x2 = 8 h is the solution
Explanation:
Matter is changed from one state to another by addition or removal of heat and suitable pressure conditions.
When a solid is heated, it normally melts and changes to liquids which on heating changes to vapor. The randomness of the particles increases from solid to liquid state and to gaseous states.
Also, a gas can be cooled to liquid and on further cooling transformed into a solid matter.
These phase changes are brought about by energy changes in a system. Some form of matter can also sublime by changing form solid to gas and vice versa.
The work done to push the refrigerator is 500 Nm.
Explanation:
Work done is the measure of force required to move any object from one point to another. So it is calculated as the product of force and displacement.
If the force increases the work done will increase and similarly, the increase in displacement increases the work done. So to push the refrigerator work should be done on the object and not by the object.
As the force is 100 N and the displacement is 5 m then, work done can be measured as
Work = Force × Displacement
Work = 100 × 5 = 500 Nm
So the work done to push the refrigerator is 500 Nm.
Answer:
Answer is explained in the explanation section below.
Explanation:
Solution:
We know that the Electric field inside the thin hollow shell is zero, if there is no charge inside it.
So,
a) 0 < r < r1 :
We know that the Electric field inside the thin hollow shell is zero, if there is no charge inside it.
Hence, E = 0 for r < r1
b) r1 < r < r2:
Electric field =?
Let, us consider the Gaussian Surface,
E x 4 
= 
So,
Rearranging the above equation to get Electric field, we will get:
E = 
Multiply and divide by 
E = x 
Rearranging the above equation, we will get Electric Field for r1 < r < r2:
E= (σ1 x ) /(
x )
c) r > r2 :
Electric Field = ?
E x 4 = 
Rearranging the above equation for E:
E = 
E = + 
As we know from above, that:
= (σ1 x ) /( x )
Then, Similarly,
= (σ2 x 
) /( x )
So,
E = +
Replacing the above equations to get E:
E = (σ1 x ) /( x ) + (σ2 x ) /( x )
Now, for
d) Under what conditions, E = 0, for r > r2?
For r > r2, E =0 if
σ1 x = - σ2 x
Answer: Distance= 100,000 km
Mass= 15 million kg Mass= 5 million kg
