All categories

3 years ago

A swimmer swims 40 miles in 80 seconds. What is the swimmer’s average speed?

Physics

1 answer:

Mamont248 [21]3 years ago

6 0

Answer:2

Explanation:

You might be interested in

Skateboard A Force: 33 N Time: 0.12 s Skateboard B Force: 33 N Time: 0.57 s Skateboard C Force: 33 N Time: 0.78 s Which skateboa

nata0808 [166]

The impulse is given by the magnitude of the force times the time interval:
$I= F \Delta t$
We can see that the force F of the 4 skateboard is always the same (33 N), this means that the skateboard with greatest impulse is the one with the largest time interval, so skateboard C).

7 0

2 years ago

Read 2 more answers

Assume that the surface temperature of the lightbulb filament when it is plugged into an outlet of 120 V is about 3000 K and the

myrzilka [38]

Answer:

A= $8.7\times 10^{-7}m^{2}$

Explanation:

We have given power =40 W but only 10% of this power is used so actual power $P=\frac{40\times 10}{100}=4 W$

We know that from Stefan's law $p=\sigma AT^4$ where $\sigma$ is Boltzmann constant which value is $5.6\times 10^{-8}Wm^{-2}K^{-4}$

So $4=5.67\times 10^{-8}\times A\times 3000^4$

A= $8.7\times 10^{-7}m^{2}$

4 0

2 years ago

Read 2 more answers

A fighter plane is flying overhead at mach 1.20. What angle does the wave front of the shock wave produced make relative to the

Sever21 [200]

Answer: 56.44°

Explanation:

Given:

Let u represent the current speed of the plane, 1.2 Mach

Converting to SI Units (m/s):

= (1.2 mach)(340 ms^-1 / 1 Mach)

u = 408 m/s

Speed of sound in air, v = 340 m/s

Find:

Angle the wave front of the shock wave relative to the plane's direction of motion, θ

We have, sinθ = speed of sound / speed of object

sinθ = v / u

θ = sin^-1 (v / u)

= sin^-1 (340 / 408)

θ = 56.44°

7 0

1 year ago

The figure (Figure 1) shows the velocity of a solar-powered motorhome (RV) as a function of time. The driver accelerates from a

SpyIntel [72]

Explanation :

It is given that, the driver accelerates from a stop sign, cruises for 20 s at a constant speed of 60 km/h, and then brakes to come to a stop 40 s after leaving the stop sign.

We know that acceleration is defined as the rate of change of velocity.

$a=\dfrac{dv}{dt}$

Where

dv is the change in velocity, dv = 0 - 60 m/s = -60 m/s

dt is the change in time, dt = 40 s - 30 s = 10 s

So, $a=\dfrac{-60\ m/s}{10\ s}$

$a = -6\ m/s^2$

From the graph it is clear that, from 30 s to 40 s the car is decelerating. So, at every second within this time the value of acceleration will be same i.e. $-6\ m/s^2$ .

6 0

2 years ago

Answer the following question according to formal grammatical rules.

VARVARA [1.3K]

Answer:

Explanation:

just trying to follow basic grammar.

5 0

2 years ago