Answer:
The final velocity of the ball is 7m/s
Explanation:
M1=8kg, V1 =10m/s
, M2=2kg
, V2=-5m/s
initial momentum before collison
m1v1+m2v2
=8×10 +2×(-5) =80-10 = 70kg m/s
final momentum after collison
=(m1+m2)×v
=(8+2)×v
=10v
According to the law of conversion of momentum
initial momentum =final momentum
70=10v
10v=70
v=70/10
v=7m/s
A.
The invasive shrimp will begin to overpower the native shrimp population, as predators will not like to eat the invasive species as much.
Answer:
(a) Eₐ = 6.36 J/s
(b) Eₐ = 4.64 J/s
Explanation:
Stefan-Boltzmann law: States that the total energy per second radiated or absorbed by a black body is directly proportional to the absolute temperature.
Using, Stefan-Boltzmann equation
Eₐ =eσAT⁴ ................ Equation 1
where Eₐ = Radiant energy absorbed per seconds, e = emissivity, σ = stefan - boltzman constant, A = Surface area. and T = temperature in kelvin
(a) Where e = 0.89, σ = 5.67 ×10⁻⁸ watt/m²/K⁴, A = 140 cm² = 140 cm²(m²/10000cm²) = 0.014 m², T = 35 °C = (35 + 273) K = 308 K.
Applying these values in equation 1 above,
Eₐ = 0.89 × 5.67 ×10⁻⁸ × 0.014 × (308)⁴
Eₐ =6.36 J/s
(b) when e = 0.65,
∴ Eₐ = 0.65 × 5.67 × 10⁻⁸ × 0.014 × (308)⁴
Eₐ = 4.64 J/s
Answer:
120 rpm
Explanation:
I1 = 105 kgm^2, I2 = 70 kgm^2
f1 = 80 rpm, f2 = ?
Let the angular speed be f2 when his arms are tucked.
If no external torque is applied, then the angular momentum remains constant.
L1 = L2
I1 w1 = I2 w2
I1 x 2 x 3.14 x f1 = I2 x 2 x 3.14 x f2
105 x 80 = 70 x f2
f2 = 120 rpm
Answer:
Magnification m is 2.5cm
Explanation:
This problem bothers on lenses
Given data
Object distance u= 4cm
Height of object v= 10 cm
The problem is quite straightforward seeing that object and image distances are given
We know that the magnification
m= size of image/size of object
m= v/u= 10/4 = 2. 5cm
What is a convex lens
A convex lens is a type of lens that has the centre thicker than the ends, the thickness at the centre makes the lens surface to curve outward. Convex lens causes close light rays of light to converge at a point after refraction.