Answer:
Explanation:
a )
hear energy required to melt 1 g of ice = 340 J ,
hear energy required to melt 80 g of ice = 340 x 80 J = 27220 J .
b ) energy gained by the melted ice ( water at O°C ) = m ct
where m is mass of water , s is specific heat and t is rise in temperature
= 80 x 4.2 x ( 8°C - 0°C)
= 2688 J .
c )
energy lost by lime juice = energy gained by ice and water
= 27220 J + 2688 J .
= 29908 J .
d )
Let specific heat required be S
Heat lost by lime juice = M S T
M is mass of lime juice , S is specific heat , T is decrease in temperature
= 320 g x S x ( 29 - 8 )°C
= 6720 S
For equilibrium
Heat lost = heat gained
6720 S = 29908 J
S = 4.45 J /g °C .
Given that,
Height =1.5 m
Angle = 45°
We need to find the greater speed of the ball
Using conservation of energy
Here, initial velocity and final potential energy is zero.
Put the value into the formula
Hence, the greater speed of the ball is 5.42 m/s.
Answer:
The tension in the string is 16.24 N
Explanation:
Given;
mass of the sphere, m = 1.55 kg
initial velocity of the sphere, u = 2.81 m/s
final velocity of the sphere, v = 4.60 m/s
duration of change in the velocity, Δt = 2.64 s
The tension of the string is calculated as follows;
T = 1.55(0.678 + 9.8)
T = 1.55(10.478)
T = 16.24 N
Therefore, the tension in the string is 16.24 N
<span>1.0 gram (g) of electrons would contain 10^27 electrons
Electrons have an electric charge of −1.602×10−19 coulomb
so total charge of 1 g electrons = -1.602 x 10^-19 x 10^27 = -1.602 x 10^8</span>
2 water molecules contain 4 hydrogen atoms and 2 oxygen atoms. a mile of water molecules contains 2 moles of hydrogen atoms and 1 mole of oxygen atoms !
hope this helped :)
