Answer:21.45 m/s
Explanation:
Given
Mass of sport car=920 kg
Mass of SUV=2300 kg
distance to which both car skid is 2.4 m
coefficient of friction ()=0.8
Let u be the initial velocity of both car at the starting of skidding
and they finally come to zero velocity
s=2.4 m
u=6.13 m/s
so before colliding sport car must be travelling at a speed of
(conserving momentum)
v=21.45 m/s
Answer:
1. the electric potential energy of the electron when it is at the midpoint is - 2.9 x J
2. the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge is - 5.04 x J
Explanation:
given information:
= 3 nC = 3 x
C
= 2 nC = 2 x
C
r = 50 cm = 0.5 m
the electric potential energy of the electron when it is at the midpoint
potential energy of the charge, F
F = k
where
k = constant (8.99 x )
electron charge, = - 1.6 x
C
since it is measured at the midpoint,
r =
= 0.25 m
thus,
F =
= k + k
= (
)
= (8.99 x )( - 1.6 x
)(3 x
+2 x
)/0.25
= - 2.9 x J
the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge
= 10 cm = 0.1 m
= 0.5 - 0.1 = 0.4 m
F = k + k
= (
+
)
= (8.99 x )( - 1.6 x
)(3 x
/0.1+2 x
/0.4)
= - 5.04 x J
Answer:
Explanation:
The energy of a photon is given by:
where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
In this problem, we have a microwave photon with wavelength
Substituting into the equation, we find its energy: