Answer:
b. 600,000 J
Explanation:
Applying the law of conservation of energy,
The thermal energy created = Kinetic energy of the suv.
Q' = 1/2(mv²)............... Equation 1
Where Q' = Thermal energy, m = mass of the suv, v = velocity of the suv.
From the question,
Given: m = 3000 kg, v = 20 m/s
Substitute these values into equation 1
Q' = 1/2(3000×20²)
Q' = 600000 J
Hence the right option is b. 600,000 J
Answer:
The answer is C
Explanation:
The magnitude of the gravitational force depends inversely on the square of the radial distance between the centers of the two masses. Thus, essentially, the force can only fall to zero, when the denominator that is r becomes infinite.
Answer: Frequency factor A = 8 × 10⁹
activation energy Ea = 15.5 KJ/Mol
Explanation: to begin, let us first define the parameters given;
K₁ = 1.44 × 10⁷dm³mol⁻¹s⁻¹
K₂ = 3.03 × 10⁷ dm³mol⁻¹s⁻¹
K₃ = 6.9 × 10 dm³mol⁻¹s⁻¹
also T₁ = 300.3 K
T₂ = 341.2 K
T₃ = 392.2 K
we know that;
㏑ K₂ / K₁ = Ea/R [1/T₁ -1/T₂]
where R is given as 8.314 J/mol-k
Ea = activation energy
K₁, K₂ = rate constant
T₁, T₂ = Temperature
therefore, ㏑ (3.03 × 10⁷/ 1.44 × 10⁷) = Ea / 8.314 [1/300.3 - 1/341.2]
this gives Ea = 15496.16 J/Mol ≈ 15.5 KJ /Mol
∴ Ea = 15.5 KJ/ Mol
also given that K = A e⁻∧Ea/RT
here A = frequency factor
∴ 6.9 × 10⁷ = A e⁻ ∧(15496.16/8.314 × 392.2)
A = 7.99 × 10⁹ = 8 × 10⁹
Answer:
Ultraviolet wave
Explanation:
Ultraviolet waves would be best used to sterilize a surface expose to bacteria because it will completely destroy them.
Most medical equipment are usually sanitized by using this rays because the DNA of most bacteria can be innervated upon exposure to these ray.
Ultraviolet rays are energetic and more powerful than the normal visible light and subsequent long wavelength radiations.
Generally, ultraviolet rays is a very harmful electromagnetic radiation.
Answer:
a= 8.74 m/s²
Explanation:
Given that
m = 21 kg
θ = 13◦
F= 210 N
g= 9.8 m/s²
The force due to gravity
F₁= m g sinθ
F₁=12 x 9.8 x sin 13◦
F₁=26.45 N
Lets take acceleration is a m/s²
Form Newtons second law
F - F₁ = m a
210 - 26.45 = 21 x a
a= 8.74 m/s²
