Apply the combined gas law
PV/T = const.
P = pressure, V = volume, T = temperature, PV/T must stay constant.
Initial PVT values:
P = 1atm, V = 8.0L, T = 20.0°C = 293.15K
Final PVT values:
P = ?, V = 1.0L, T = 10.0°C = 283.15K
Set the PV/T expression for the initial and final PVT values equal to each other and solve for the final P:
1(8.0)/293.15 = P(1.0)/283.15
P = 7.7atm
The wavelength

of the wave is 160 m, and this is the distance between two consecutive crests. The boat is located at a crest of the wave, this means that the first trough is located 80 meters from the boat (because the distance between a crest and a trough is half the wavelength).
The speed of the wave is

so the time the boat takes to reach the first trough is
Answer: The initial force is reduced a factor 1/4 when the separation between charge is doubled
Explanation: As it well known the electric force between two charges is given by:
Finitial=k*q1*q2/d^2 where d is the distance between charges and k is a constant
if the distance is doubled this means 2*dinitial thus the new force is equal to F initial* 1/4
Answer:D
Explanation:
Given
mass of object 
Distance traveled 
velocity acquired 
conserving Energy at the moment when object start falling and when it gains 12 m/s velocity
Initial Energy
Final Energy

where
is friction work if any


Since Friction is Present therefore it is a case of Open system and net external Force is zero
An open system is a system where exchange of energy and mass is allowed and Friction is acting on the object shows that system is Open .