Kinetic energy =0.5*mas*velocity^2
Joules =lg*m^2/s^2
1 miles= 1608.34 meters
1 hour= 3600 Sec
1 ounce =28.35g =0.02836 kg
What is a the kinetic energy, in joules, of this baseball when it is thrown by a major-league pitcher at 96.0 mi/h?
Answer: KE=0.5m*v^2
=0.5*(5.12 o *0.02835 kg/1 ounce)* (95 miles/h*1609.34m/1 miles* 1hr/3600s^)2
131kg*m^2/s^2= 131 joules
By what factor with the kinetic energy change if the speed of the baseball is decreased to 55.0 mi/h?
Answer: KE=0.5*m*v^2
=0.5*(5.13 o*0.02835kg/1 ounce)*(55 miles/ h*1609.34m/1 mile*1 hr/3600s)^2
=44.0kg*m^2s^2=44.0 joules
131/44= 2.98, so decreased by a factor of approximately 3
The protons and electrons are held in place on the x axis.
The proton is at x = -d and the electron is at x = +d. They are released at the same time and the only force that affects movement is the electrostatic force that is applied on both subatomic particles. According to Newton's third law, the force Fpe exerted on protons by the electron is opposite in magnitude and direction to the force Fep exerted on the electron by the proton. That is, Fpe = - Fep. According to Newton's second law, this equation can be written as
Mp * ap = -Me * ae
where Mp and Me are the masses, and ap and ae are the accelerations of the proton and the electron, respectively. Since the mass of the electron is much smaller than the mass of the proton, in order for the equation above to hold, the acceleration of the electron at that moment must be considerably larger than the acceleration of the proton at that moment. Since electrons have much greater acceleration than protons, they achieve a faster rate than protons and therefore first reach the origin.
You can't find the acceleration of the ball. The graph tells the force, but you'd also need to know the mass of the ball.
Apply Gay-Lussac's law:
P/T = const.
P = pressure, T = temperature, the quotient of P/T must stay constant.
Initial P and T values:
P = 180kPa, T = -8.0°C = 265.15K
Final P and T values:
P = 245kPa, T = ?
Set the initial and final P/T values equal to each other and solve for the final T:
180/265.15 = 245/T
T = 361K
