Answer :
Image distance = -2.4 cm
Height of image = 7.2 cm
Concave lens
Explanation :
Given that,
Height of the object, h = 9 cm
Object distance, u = 3 cm
Focal length, f = -12 cm
Using mirror's formula
v = -2.4 cm
Image distance is 2.4 cm from the lens.
Magnification,
h' = 7.2 cm
The height of the image is 7.2 cm. This shows that the image is upright.
The lens used is concave lens.
The specific heat of mercury is 149.4 J/(kgK)
Explanation:
When a substance is supplied with an amount of energy Q, its temperature increases according to the equation:
where
is the increase in temperature
m is the mass of the sample
is its specific heat capacity
For the sample of mercury in this problem we have
Q = 275 J
m = 0.450 kg
Therefore, by re-arranging the equation we find the mercury's specific heat:
Learn more about specific heat capacity:
#LearnwithBrainly
Answer:
(4xy+5ab)(4xy-5ab)
Explanation:
16-25
4^2 is 16 and 5^2 is 25,
Also, (x-a)(x+a) = x^2-a^2
So, this factorized is:
(4xy+5ab)(4xy-5ab)
Hope this helps!
1. C. Gravitational attraction exists between the two objects.
Explanation:
Gravitational attraction is always exerted between two objects which have mass, and its magnitude is given by:
where G is the gravitational constant, m1 and m2 the masses of the two objects, and r the separation between them. Since the two objects have for sure non-zero masses m1 and m2, even if they are 20 miles apart, the value of the gravitational attraction F is non-zero, so the correct answer is C.
2. D. Two atoms come together to form a molecule.
Explanation:
this outcome is actually caused by the electrostatic forces between the two atoms, not by gravitational force. In fact, gravitational force becomes relevant only when the masses of the two objects involved are large enough: this is the case for planets, stars, galaxies, and objects in the universe. However, two atoms have very small masses, so the gravitational force between them is really negligible. On this smaller scales, the electrostatic force is much stronger than the gravitational force, so the electrostatic force is the real responsible for the formation of bonds between atoms.