KE = kinetic energy
PE = potential energy
GPE = gravitational potential energy
energy is always measured in Joules (J)
KE = (0.5) times the mass times the velocity^2
square the velocity first
Mass = (KE x 2) / v^2
square the velocity first, then double the kinetic energy, then divide
mass is measured in kg
velocity = sqrt(KE x 2 / m)
velocity can be called speed, like in the the second problem
remember to find the square root after you double the KE and divide that by the mass.
for example: if after you doubled KE and divided it by the mass you got sqrt(20), the answer would be about 4.47
GPE = mass x gravitational pull (about 9.8 m/s^2 on earth) x height
height = (PE) / (g x m)
do g x m first
So for question 1:
KE = (0.5)0.1 x 1.1^2
always square the velocity first:
KE = (0.5)0.1 x 1.21
KE = 0.0605
so if you rounded it to the nearest hundreths you would get KE = 0.06 J
don't forget the unit of energy is in Joules
We use the formula: p = E/c where E = hc / λ. hence, p = h/ λ. where h is the Planck's constant: 6.62607004 × 10-34 m2 kg / s and <span>λ is the wavelenght.
</span>
a) p = <span>6.62607004 × 10-34 m2 kg / s / 0.1 x10^-9 m = 6.62607 x 10-24 m kg/s
</span>b) p = 6.62607004 × 10-34 m2 kg / s / 3 x10^-2 m = 2.20869 <span>x 10-32 m kg/s
</span>b) p = 6.62607004 × 10-34 m2 kg / s / 2 x10^-9 m = 3.3130 <span>x 10-25 m kg/s</span>
1km=1000m=1000000mm
118km/h=118000000 mm/h
C. Elements
elements are found in periodic table (in 1 box)
This question is incomplete, the complete question is;
A block of mass m begins at rest at the top of a ramp at elevation h with whatever PE is associated with that height. The block slides down the ramp over a distance d until it reaches the bottom of the ramp.
How much of its original total energy (in J) survives as KE when it reaches the ground? m = 9.9 kg h = 4.9 m d = 5 m μ = 0.3 θ = 36.87°
Answer:
the amount of its original total energy (in J) that survives as KE when it reaches the ground will is 358.975 J
Explanation:
Given that;
m = 9.9 kg
h = 4.9 m
d = 5 m
μ = 0.3
θ = 36.87°
Now from conservation of energy, the energy is;
Et = mgh
we substitute
Et = 9.9 × 9.8 × 4.9
= 475.398 J
Also the loss of energy i
E_loss = (umg cosθ) d
we substitute
E_loss = 0.3 × 9.9 × 9.8 × cos36.87° × 5
= 116.423 J
so the amount of its original total energy (in J) that survives as KE when it reaches the ground will be
E = Et - E_loss
E = 475.398 J - 116.423 J
E = 358.975 J
