A 10n falling object encounters 4n of air resistance. what is the net force on the object?

If a person throws a wiffle ball and a tennis ball with the same speed, which object would travel with more kinetic

yawa3891 [41]

Answer:

The tennis ball will have more kinetic energy

Explanation:

It will have more kinetic energy because the tennis ball is more heavier than a wiffle ball. Furthermore, objects that are heavy will have more kinetic energy than objects that are light. Therefore, the tennis ball is the correct answer.

5 0

3 years ago

An inventor claims to have developed a food freezer that, in steady-state conditions, requires a power input of 0.25 kW to extra

WARRIOR [948]

Answer:

The inventors claim is not real

a) No the the freezer cannot operate in such conditions

Explanation:

From the question we are told that

The power input is $P_i = 0.25 kW = 0.25 *10^{3} \ W$

The rate of heat transfer $J = 3050 J/s$

The temperature of the freezer content is $T = 270 \ K$

The ambient temperature is $T_a = 293 \ K$

Generally the coefficient of performance of a refrigerator at idea conditions is mathematically represented as

$COP = \frac{T }{Ta - T}$

substituting values

$COP = \frac{270 }{293 - 270}$

$COP =11.7$

Generally the coefficient of performance of a refrigerator at real conditions is mathematically represented as

$COP = \frac{J}{P_i}$

substituting values

$COP = \frac{3050}{0.25 *10^{3}}$

$COP = 12.2$

Now given that the COP of an ideal refrigerator is less that that of a real refrigerator then the claims of the inventor is rejected

This is because the there are loss in the real refrigerator cycle that are suppose to reduce the COP compared to an ideal refrigerator cycle where there no loss that will reduce the COP

4 0

3 years ago

790 kilometers/hour for a distance of 4,700 kilometers

chubhunter [2.5K]

Answer:

Explanation:

Time = (distance) / (average speed)

Time = (4,700 km) / (790 km/hr) = 5.9494 hours (rounded)

= 5hrs 56min 58 sec (rounded)

(4,700 km) / (1.609344 km/mile) = 2,920 miles

Speed = (distance covered) / (time to cover the distance)

(2,929 miles) / 5.9494 hours) = 491 miles per hour

5 0

2 years ago

A brick is dropped from the top of a building through the air (friction is present) to the ground below. Part A How does the bri

maria [59]

Answer:kinetic energy is less than Potential Energy at bottom

Explanation:

Given

Brick is drop from top of tower

suppose brick Potential Energy at top is U=C

Kinetic Energy(K) of brick is =0 at top of building

Just before hitting its Potential Energy is converted to kinetic energy and some is lost due to the friction.

Therefore kinetic Energy is less than the potential energy

at bottom K < U

8 0

3 years ago

The absolute potential at a distance of 2.0 m from a negative point charge is-100. V. What is the absolute potential 4.0 m away

jolli1 [7]

Answer:

The absolute potential 4.0 m away from the same point charge is -50 V.

(A) is correct option.

Explanation:

Given that,

Distance = 2.0 m

Potential = -100 V

Absolute potential = 4.0 m

We need to calculate the charge

Using formula of potential

$V=\dfrac{kq}{r}$

Where, V = potential

q = charge

r = distance

Put the value into the formula

$-100=\dfrac{9\times10^{9}\times q}{2.0}$

$q=\dfrac{200}{9\times10^{9}}$

$q=-22.2\times10^{-9}\ C$

We need to calculate the potential

Using formula of potential

$V=\dfrac{9\times10^{9}\times(-22.2\times10^{-9})}{4.0}$

$V=-49.95\ V$

$V=-50\ V$

Hence, The absolute potential 4.0 m away from the same point charge is -50 V.

6 0

2 years ago