Answer:
The electromagnetic force
Explanation:
The electromagnetic force is one of the four fundamental forces of nature. Namely, they are:
- Electromagnetic force: it is the force exerted between electrically charged particles (and between magnetic fields). The force can be either attractive (if the two charges have opposite signs) or repulsive (if the two charges have same sign), and it acts over an infinite range.
- Gravitational force: it is the force exerted between objects with mass. It is always attractive, and it also has an infinite range of action. It is the weakest of the four fundamental forces.
- Strong nuclear force: it is the force that acts between protons and neutrons inside the nucleus, and it is responsible for keeping the nucleus together and preventing it from breaking apart (due to the electrostatic repulsion between protons)
- Weak nuclear force: it is the force responsible for certains nuclear decays, such as the beta decay, in which a neutron turns into a proton, emitting an electron and an antineutrino.
Answer:
= 4.3 × 10 ⁻¹⁴ m
Explanation:
The alpha particle will be deflected when its kinetic energy is equal to the potential energy
Charge of the alpha particle q₁= 2 × 1.6 × 10⁻¹⁹ C = 3.2 × 10⁻¹⁹ C
Charge of the gold nucleus q₂= 79 × 1.6 × 10⁻¹⁹ = 1.264 × 10⁻¹⁷C
Kinetic energy of the alpha particle = 5.28 × 10⁶ × 1.602 × 10⁻¹⁹ J ( 1 eV)
= 8.459 × 10⁻¹³
k electrostatic force constant = 9 × 10⁹ N.m²/c²
Kinetic energy = potential energy = k q₁q₂ / r where r is the closest distance the alpha particle got to the gold nucleus
r = ( 9 × 10⁹ N.m²/c² × 3.2 × 10⁻¹⁹ C × 1.264 × 10⁻¹⁷C) / 8.459 × 10⁻¹³
= 4.3 × 10 ⁻¹⁴ m
Answer:
3.75 MeV
Explanation:
The energy of the photon can be given in terms of frequency as:
E = h * f
Where h = Planck's constant
The frequency of the photon is 6 * 10^20 Hz.
The energy (in Joules) is:
E = 6.63 x10^(-34) * 6 * 10^(20)
E = 39.78 * 10^(-14) J = 3.978 * 10^(-13) J
We are given that:
1 eV = 1.06 * 10^(-19) Joules
This means that 1 Joule will be:
1 J = 1 / (1.06 * 10^(-19)
1 J = 9.434 * 10^(18) eV
=> 3.978 * 10^(-13) J = 3.978 * 10^(-13) * 9.434 * 10^(18) = 3.75 * 10^(6) eV
This is the same as 3.75 MeV.
The correct answer is not in the options, but the closest to it is option C.
Explanation:
A worker picks up the bag of gravel. We need to find the speed of the bucket after it has descended 2.30 m from rest. It is case of conservation of energy. So,
h = 2.3 m
So, the speed of the bucket after it has descended 2.30 m from rest is 6.71 m/s.
Average speed = total distance travelled ÷ total time taken
AS = (75km + 68km) ÷ (1hr + 2hr)
As = 143km ÷ 3hr
AS = 47.66667 km/hr
AS = 47.7 km/hr (3sf)
