All categories

3 years ago

At a speed of 60 mph, how far does your car travel in 3 seconds

1 answer:

4 0

One of the many random useless factoids that I carry around
in my head is the factoid that 60 miles per hour is equivalent
to exactly 88 feet per second.

So in three seconds at that speed, you would cover exactly

(3 x 88) = 264 feet.

You might be interested in

A police car parked on the side of the highway emits a 1200 Hz sound that bounces off a vehicle farther down the highway and ret

emmasim [6.3K]

f' = frequency observed by the police car after sound reflected from the vehicle and comes back to police car = 1250 Hz

f = frequency emitted by the police car = 1200 Hz

V = speed of sound = 340 m/s

v = speed of vehicle = ?

frequency observed by the police car is given as

f' = f (V + v)/(V - v)

inserting the values in the above equation

1250 = 1200 (340 + v)/(340 - v)

v = 6.9 m/s

4 0

4 years ago

Read 2 more answers

A motorist is driving at 20m/s when she sees that a traffic light 200m ahead has just turned red. She knows that this light stay

yuradex [85]

Answer:

5.71428571422 m/s

Explanation:

u = Initial velocity = 20 m/s

v = Final velocity

s = Displacement

a = Acceleration

Time taken = 15-1 = 14 s

Distance traveled in 1 second = $20\times 1=20\ m$

$s=ut+\frac{1}{2}at^2\\\Rightarrow 200-20=20\times 14+\frac{1}{2}\times a\times 14^2\\\Rightarrow a=\frac{2(180-20\times14)}{14^2}\\\Rightarrow a=-1.02040816327\ m/s^2$

$v=u+at\\\Rightarrow v=20-1.02040816327\times 14\\\Rightarrow v=5.71428571422\ m/s$

The speed as she reaches the light at the instant it turns green is 5.71428571422 m/s

4 0

4 years ago

A car is moving at 25.5 m/s when it accelerates at 1.94 m/s^2 for 2.3 s. What is the car's final speed? (Keep in mind direction

Stolb23 [73]

Answer:

29.96m/s

Explanation:

Given parameters:

Initial speed = 25.5m/s

Acceleration = 1.94m/s²

Time = 2.3s

Unknown:

Final speed of the car = ?

Solution:

To solve this problem, we are going to apply the right motion equation:

v = u + at

v is the final speed

u is the initial speed

a is the acceleration

t is the time taken

Now insert the parameters and solve;

v = 25.5 + (1.94 x 2.3) = 29.96m/s

3 0

3 years ago

What is a force that opposes motion between two surfaces that are in contact?

choli [55]

Answer:

Friction is a force that opposes motion.

8 0

3 years ago

A horizontal compass is placed 21 cm due south from a straight vertical wire carrying a 36 a current downward. in what direction

Anit [1.1K]

The needle of a compass will always lies along the magnetic field lines of the earth.
A magnetic declination at a point on the earth’s surface equal to zero implies that
the horizontal component of the earth’s magnetic field line at that specific point lies along
the line of the north-south magnetic poles.

The presence of a current-carrying wire creates an additional 
magnetic field that combines with the earth’s magnetic field. Since magnetic
fields are vector quantities, therefore the magnetic field of the earth and the magnetic field of the vertical wire must be combined vectorially.

Where:

B1 = magnetic field of the earth along the x-axis = 0.45 × 10 ⁻ ⁴ T

B2 = magnetic field due to the straight vertical wire along the y-axis

We can calculate for B2 using Amperes Law:

B2 = μ₀ i / [ 2 π R ]

B2 = [ 4π × 10 ⁻ ⁷ T • m / A ] ( 36 A ) / [ 2 π (0.21 m ) ] 
B2 = 5.97 × 10 ⁻ ⁵ T = 0.60 × 10 ⁻ ⁴ T

The angle can be calculated using tan function:
tan θ = y / x = B₂ / B₁ = 0.60 × 10 ⁻ ⁴ T / 0.45 × 10 ⁻ ⁴ T 
tan θ = 1.326

θ = 53°

The compass needle points along the direction of 53° west of north.

8 0

4 years ago