Answer:
a) 5.851× 10¹⁰m/s²
b) 2.411×10⁻¹¹s
c) 1.70×10⁻¹¹m
d) 1.661×10⁻²⁷KJ
Explanation:
A proton in the field experience a downward force of magnitude,
F = eE. The force of gravity on the proton will be negligible compared to the electric force
F = eE
a= eE/m
= 1.602×10⁻¹⁹ × 610/1.67×10⁻²⁷
= 5.851× 10¹⁰m/s²
b)
V = u + at
u= 0
v= 1.4106m/s
v= (0)t + at
t= v/a
= 1.4106m/s/5.851 ×10¹⁰
= 2.411×10⁻¹¹s
c)
S = ut + at²
= (o)t + 5.851×10¹⁰×(2.411×10⁻¹¹)²
= 1.70×10⁻¹¹m
d)
Ke = 1/2mv²
= (1.67×10⁻²⁷×)(1.4106)²/2
= 1.661×10⁻²⁷KJ
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.
When you heat something of cool it down you don't change the substance you might change the why is looks, but it is still the same substance. For example you cool water to 0 degrees Celsius it turns into ice but it still is two parts hydrogen and one part oxygen H2O. Physical changes will change state and/or form but it will still be what it originally was on the molecular level. Hope that helped.
Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
-
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
-
)
= 0.2(
)
f =
= 150
For air (nair = 1):
= (1.5 - 1)(
-
)
f =
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.