Answer:
Option (b)
Explanation:
Let the ball takes time t to reach the maximum height. The final velocity at maximum height is zero.
Use I equation of motion, we get
V = u + gt
0 = 3 - 9.8 x t
t = 0.306 s
As the air friction is negligible, so the ball takes same time to reach the hand of boy. Thus the time taken by the ball in air is
T = 2 t = 2 x 0.306 = 0.61 s
Answer:
JC⁻¹
Explanation:
= mass of water added to calorimeter = 94.8 g
= initial temperature of the water added = 60.4 C
= specific heat of water = 4.184 Jg⁻¹C⁻¹
= mass of water available to calorimeter = 94.8 g
= initial temperature of the water in calorimeter = 22.3 C
= final equilibrium temperature = 35 C
= Heat gained by calorimeter
Using conservation of heat
Heat gained by calorimeter = Heat lost by water added - heat gained by water in calorimeter
J
= Change in temperature of calorimeter
Change in temperature of calorimeter is given as
C
Heat capacity of calorimeter is given as
JC⁻¹
Answer:
Reversal of Earths magnetic field
Explanation:
Earth’s magnetic field reverses direction approximately every 2 million years. Every time Earths magnetic Field reverses, the magnetic direction of new sea floor along mid-ocean ridges also reverses. These alternating layers of magnetized seafloor can be used to map out boundaries of diverting plates.
The answer is the third choice, "the brightness of the beam of light increases"
According to Einstein’s theory, an increase in the number of photons (per unit are) affects a beam of light by causing a higher intensity. <span> Sometimes, the term "brightness" is used when referring to the </span>intensity<span> of a color, a</span><span>lthough there are instances where this can be a misleading term when we try to describe </span><span>intensity</span>
The plates push apart from eachother