Efficiency = useful energy out / total energy in x 100
= 100/400 x 100
=0.25 x 100
= 25%
25%
Answer:
elements in the same column have the same number of neutrons. elements with similar mass are placed in the same column.
The coefficient of friction must be 0.196
Explanation:
For a car moving on a circular track, the frictional force provides the centripetal force needed to keep the car in circular motion. Therefore, we can write:
where the term on the left is the frictional force acting between the tires of the car and the road, while the term on the right is the centripetal force. The various terms are:
is the coefficient of friction between the tires and the road
m is the mass of the car
is the acceleration of gravity
v is the speed of the car
r is the radius of the curve
In this problem,
r = 750 m is the radius
is the speed
And solving for
, we find the coefficient of friction required to keep the car in circular motion:

Learn more about circular motion:
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Answer: EL ZINC ES EL ELEMENTO PURO PORQUE NO HA REACCIONADO CON NINGÚN OTRO METAL O NO METAL. EL SULFURO DE ZINC ES UN COMPUESTO PORQUE HA REACCIONADO CON EL AZUFRE PARA HACER EL COMPUESTO.
english:
ZINC IS THE PURE ELEMENT BECAUSE IT HAS NOT REACTED WITH ANY OF OTHER METAL OR NONMETAL. ZINC SULPHIDE IS A COMPOUND BECAUSE IT HAS REACTED WITH SULPHUR TO MAKE COMPOUND.