m = mass of the ice added = ?
M = mass of water = 1.90 kg
= specific heat of the water = 4186 J/(kg ⁰C)
= specific heat of the ice = 2000 J/(kg ⁰C)
= latent heat of fusion of ice to water = 3.35 x 10⁵ J/kg
= initial temperature of ice = 0 ⁰C
= initial temperature of water = 79 ⁰C
T = final equilibrium temperature = 8 ⁰C
using conservation of heat
Heat gained by ice = Heat lost by water
m (T - ) + m = M ( - T)
inserting the values
m (4186) (8 - 0) + m (3.35 x 10⁵ ) = (1.90) (4186) (79 - 8)
m = 1.53 kg
Answer:
630cm/s
Explanation:
In simple harmonic motion, the tangential velocity is expressed mathematically as v = ὦr
ὦ is the angular velocity = 2πf
r is the radius of the disk
f is the frequency
Given the radius of disk = 10cm
frequency = 10Hz
v = 2πfr
v = 2π×10×10
v = 200π
v = 628.32 cm/s
The tangential velocity = 630cm/s ( to 2 significant figures)
Answer:
Beats is a phenomenon which occurs when two sound waves with different frequencies overlap each other.
Explanation:
When these two sound waves overlap, a third frequency is formed. The places where the two waves reinforces each other, constructive interference takes place and a louder sound is produced whereas, at points where destructive interference takes place a softer sound is produced.
These alternative loud and soft sounds are called beats.
Answer:
current, only
Explanation:
current:I
voltage:U
resistance:R
formula: I=U/R
Increasing the battery cause the increasing in the voltage. Resistance does not normally change. And the current would increase.
Answer:
the energy when it reaches the ground is equal to the energy when the spring is compressed.
Explanation:
For this comparison let's use the conservation of energy theorem.
Starting point. Compressed spring
Em₀ = K_e = ½ k x²
Final point. When the box hits the ground
Em_f = K = ½ m v²
since friction is zero, energy is conserved
Em₀ = Em_f
1 / 2k x² = ½ m v²
v = 
x
Therefore, the energy when it reaches the ground is equal to the energy when the spring is compressed.
