From the concept of optics on a curvature of a spherical mirror, the proportion for which the focal length is equivalent to half the radius of curvature is fulfilled. Mathematically this is
Here,
f = Focal Length
R = Radius
Rearranging to find the radius we have,
Replacing with our values,
R = 2(13.8cm)
R = 27.6cm
Therefore the radius of the spherical surface from which the mirror was made is 27.6cm
All machines are not 100% efficient because of <span>C. Friction</span>
F = force applied to stop the car = - 3000 N
m = mass of the car = 3000 kg
a = acceleration of the car = ?
v₀ = initial velocity of the car before the force is applied to stop it = 10 m/s
v = final velocity of the car when it comes to stop = 0 m/s
d = stopping distance of the car
acceleration of the car is given as
a = F/m
inserting the values
a = - 3000/3000
a = - 1 m/s²
using the kinematics equation
v² = v²₀ + 2 a d
inserting the values
0² = 10² + 2 (-1) d
0 = 100 - 2 d
2 d = 100
d = 100/2
d = 50 m
hence the correct choice is
C. 50 m
Answer:
2361 Newtons
Explanation:
From the second Newton's law of motion;
F = ma
In this case;
we are given;
Mass as 9.5 g
Initial speed as 0 m/s
Final velocity as 650 m/s
Distance is 0.85 m
Using the equation;
V² = U² + 2as
But u = 0
v² = 2as
Therefore;
a = v² ÷ 2s
= 650² ÷ 2(0.85)
= 248,529.40 m/s²
But;
F = ma
= 0.0095 kg × 248,529.40 m/s²
= 2361 Newtons
Therefore;
The average net force required to accelerate the bullet is 2361 Newtons.
Answer: The weight of a 72.0 kg astronaut on the Moon is 117.36 N.
Explanation:
Mass of the astronaut on the moon , m= 72 kg
Acceleration due to gravity on moon,g = 1.63 
According to Newton second law of motion: F = ma
This will changes to = Weight = mass × g
The weight of a 72.0 kg astronaut on the Moon is 117.36 N.
