Question

The de Broglie wavelength of a neutron is 144 pm. What is its velocity ?

Answer 1

λ

=

h

m

v

h is the Planck constant =

6.63

×

10

−

34

x

J

s

λ

is the wavelength = 144 pm =

1.44

×

10

−

10

x

m

m

=

1.67

×

10

−

27

x

k

g

∴

v

=

h

m

λ

v

=

6.63

×

10

−

34

1.67

×

10

−

27

×

1.44

×

10

−

10

x

m/s

v

=

2.77

×

10

3

x

m/s