Answer:
D
Explanation:
cuz it transforms from one to another can't be created not destroyed.PERIOD!
C. Sugars dissolved in water
Answer:
The greatest speed of the car is 19.36m/s
Explanation:
The maximum speed the car will attain without skidding is given by:
F= uN = umg ...eq1
But F = mv^2/r
mv^2/r = umg
Dividing both sides by m, leaves you with:
V= Sqrt(ugr)
Where u = coefficient of static friction
g = acceleration due to gravity
r = raduis
Given:
U = 0.82
r=0.82
g= 9.8m/s
V = Sqrt(0.82 × 9.8 × 45)
V = Sqrt(374.85)
V = 19.36m/s
Answer:
The voltage across a semiconductor bar is 0.068 V.
Explanation:
Given that,
Current = 0.17 A
Electron concentration 
Electron mobility 
Length = 0.1 mm
Area = 500 μm²
We need to calculate the resistivity
Using formula of resistivity


Put the value into the formula


We need to calculate the resistance
Using formula of resistance



We need to calculate the voltage
Using formula of voltage

Put the value into the formula


Hence, The voltage across a semiconductor bar is 0.068 V.
Answer:
D. Both occur between objects independently whether they are in contact or not.
Explanation:
- The gravitational force is a force that is exerted between two (or more) objects having mass. This force is always attractive and its magnitude is given by

where G is the gravitational constant, m1 and m2 are the two masses, and r is the distance between the two masses.
- The electrical force is a force that is exerted between two (or more) objects having electrical charge. It can be either attractive or repulsive, depending on the sign of the two charges, and its magnitude is given by

where k is the Coulomb's constant, q1 and q2 are the two charges, and r the distance between the two charges.
Looking at both formulas, we see that the two forces are present even when the two objects are not in contact with each other (in fact, r can assume any value in the formula). They are said to be non-contact forces. Therefore, the correct option is
D. Both occur between objects independently whether they are in contact or not.