Answer: 1.76 s
Explanation:
We have the following data:
is the total mass of the bike and the rider
is the initial velocity
is the force applied to the brakes
Firstly, we will find the acceleration
with the following equation:
(1)
Isolating
:
(2)
(3)
(4) This is the magnitude of the acceleration, however, since the final velocity is 0 m/s, this means the direction is negative
Hence:
(5)
On the other hand, with the following equation we can find the time
:
(6)
Where:
is the final velocity (the bike stops)
Isolating
:
(7)
(8)
Finally:
This iste time it takes to the bike to stop
Impulse equals to the force into the actual time period of the applied force . thus the force here given is 245.300 N and time is 0.05 thus the impulse is 12.265 Ns
Answer:
electron λ = 12.5 nm
, bullet λ = 1.11 10⁻³³ m and golf ball λ = 4.7 10⁻³⁴ m
Explanation:
The Broglie wave duality principle states that all matter has wave and particle properties, it is expressed by the equation
p = h / λ
Where lam is called broglie wavelength
Let's use the definition of momentum
p = mv
Let's calculate the wavelengths
-Electron
mv = h /λ
λ = h / mv
λ = 6.63 10⁻³⁴ / (9.1 10⁻³¹ 5.81 10⁶)
λ = 1.25 10⁻¹⁰ m
λ = 12.5 nm
This is the X-ray region
-bullet
λ = 6.63 10⁻³⁴ / (1.90 10⁻³ 313)
λ = 1.11 10⁻³³ m
It is too small, only particle characteristics are observed
-Golf ball
λ = 6.63 10⁻³⁴ / (4.50 10⁻² 31.3)
λ = 4.7 10⁻³⁴ m
Too small, only particle characteristics are visible
Answer:
b
Explanation:
When an object is in circular motion, the direction of velocity is in the direction of tangent to the circle and acceleration is always directed towards the radial direction. This means that velocity is always perpendicular to acceleration of the object.
Hence option (b)-The velocity and acceleration vectors are perpendicular is correct.
Answer:
A= 150 J
Explanation:
Kinetic energy is the energy of an object in motion.
The formula for kinetic energy is ;
K.E = 1/2 * m *v² where m is mass and v is velocity
Work done is equal to change in kinetic energy
W= Δ K.E
Given that K.E = 150 J
Taking that the ball was stationary before it was thrown, this makes its initial kinetic energy to be 0 J so the work done will be
W= Δ K.E
W= 150 - 0
W= 150 J