<em>Answer</em>
Force = 170 N
<em>Explanation</em>
First find the distance (d) travelled by the bulldozer.
Sin 35 = 15/d
d = 15/(sin 35)
= 26.15m
Now;
work done = force × distance.
4500 J = force × 26.15
dividing both sides by 26.15,
Force = 4500/26.15
= 172.07 N
Answer to two significant figures = 170 N
Answer:
13 m/s
Explanation:
Given:
Δy = 8.2 m
v₀ = 0 m/s
a = 9.8 m/s²
Find: v
v² = v₀² + 2aΔy
v² = (0 m/s)² + 2 (9.8 m/s²) (8.2 m)
v = 12.7 m/s
Rounded to two significant figures, the speed is 13 m/s.
Answer:
0.15 mV
Explanation:
In order to exhibit wave nature, the de Broglie wavelength of the electron must be of the same size of the diameter of the pinhole, therefore:
The de Broglie wavelength of an electron is
where
is the Planck constant
is the mass of the electron
v is the electron's speed
Therefore, the electron's speed must be
When accelerated through a potential difference 
, the kinetic energy gained by the electron is equal to the change in electric potential energy, therefore
where
is the magnitude of the charge of the electron
So, we can find the potential difference needed:
