Mechanical waves nees a material medium to propagate
Electromagnetic waves can propagate in vaccum
Static friction opposes the movement of car from the state of rest.
Dynamic or kinetic friction opposes the movement of the car when car is running at any speed.
Answer:
t=67.7s
Explanation:
From this question we know that:
Vo = 6m/s
a = 1.8 m/s2
D = 1500m
And we also know that:
Replacing the known values:
Solving for t we get 2 possible answers:
t1 = -44.3s and t2 = 67.7s Since negative time represents an instant before the beginning of the movement, t1 is discarded. So, the final answer is:
t = 67.7s
Answer:
The value is
Explanation:
Generally from the calorimetry principle we have that

So here heat gained water is mathematically represented as i.e

substituting 0.150 kg for
, 4200 J/kg.°C for
, 100°C for
and 75°C for T
We have


The Heat loss by the ice is mathematically represented as

Here
is the energy to move the ice to its melting point which is evaluated as

Here
is the mass of ice
is the specific heat of ice with value 
temperature of ice at melting point with value 0°C
is the temperature of ice with value -12°C
is the energy to move the ice from its its melting point to liquid which is evaluated as

Here L is the Latent heat of melting of ice with value 
is the energy to move the ice from liquid to the equilibrium temperature which is evaluated as

So
![Q_i = m_i [ c_i * ( T_o -T_i) + L + c_w * ( T -T_o) ]](https://tex.z-dn.net/?f=Q_i%20%20%3D%20m_i%20%5B%20c_i%20%2A%20%28%20T_o%20-T_i%29%20%2B%20L%20%20%2B%20c_w%20%2A%20%28%20T%20-T_o%29%20%5D%20)
=> ![Q_i = m_i [ 2.05 * 10^3 * ( 0 -(-12)) + 334 * 10^3 + 4200 * ( 75 - 0) ]](https://tex.z-dn.net/?f=Q_i%20%20%3D%20m_i%20%5B%202.05%20%2A%2010%5E3%20%2A%20%28%200%20-%28-12%29%29%20%2B%20334%20%2A%2010%5E3%20%20%2B%20%204200%20%2A%20%28%2075%20-%200%29%20%5D%20)
From

We have that
=>
=>