What's the momentum (in kg-m/s) of a cannonball with a mass of 21 moving with a velocity of 25 m/s?

A 975-kg sports car (including driver) crosses the rounded top of a hill at determine (a) the normal force exerted by the road o

iVinArrow [24]

There are missing data in the text of the problem (found them on internet):
- speed of the car at the top of the hill: $v=15 m/s$
- radius of the hill: $r=100 m$

Solution:

(a) The car is moving by circular motion. There are two forces acting on the car: the weight of the car $W=mg$ (downwards) and the normal force N exerted by the road (upwards). The resultant of these two forces is equal to the centripetal force, $m \frac{v^2}{r}$ , so we can write:
$mg-N=m \frac{v^2}{r}$ (1)
By rearranging the equation and substituting the numbers, we find N:
$N=mg-m \frac{v^2}{r}=(975 kg)(9.81 m/s^2)-(975 kg) \frac{(15 m/s)^2}{100 m}=7371 N$

(b) The problem is exactly identical to step (a), but this time we have to use the mass of the driver instead of the mass of the car. Therefore, we find:
$N=mg-m \frac{v^2}{r}=(62 kg)(9.81 m/s^2)-(62 kg) \frac{(15 m/s)^2}{100 m}=469 N$

(c) To find the car speed at which the normal force is zero, we can just require N=0 in eq.(1). and the equation becomes:
$mg=m \frac{v^2}{r}$
from which we find
$v= \sqrt{gr}= \sqrt{(9.81 m/s^2)(100 m)}=31.3 m/s$

7 0

3 years ago

[10 POINTS ❗️❗️ and brainlist :)]

ludmilkaskok [199]

The answer to this is D

6 0

2 years ago

Read 2 more answers

13. in batesian mimicry, a palatable species gains protection by mimicking an unpalatable one. imagine that individuals of a pal

fiasKO [112]

Batesian mimicry is an adaptive feature associated with the coloration of a given species in a given environment.

<h3>What is Batesian mimicry?</h3>

Batesian mimicry can be defined as a type of adaptive feature associated with the coloration of a particular species and/or population.

On the first island, the color of the population won't change because of the absence of predators.

On the second island, the color of the population will change because of the presence of predators that can be alerted by the color.

On the third island, the color of the population won't change because of the presence of a species with a similar color.

In conclusion, Batesian mimicry is an adaptive feature associated with the coloration of a given species in a given environment.

Learn more about Batesian mimicry here:

brainly.com/question/14139071

#SPJ1

6 0

2 years ago

The presently accepted value of the hubble constant gives an age of

koban [17]

Answer:

14 billion years

Explanation:

The Hubble – Lemaître law, previously called the Hubble law, is a law of physics that states that the redshift of a galaxy is proportional to the distance it is, which is the same as, the further one galaxy is found from another, more quickly it seems to move away from it.

The Hubble constant is the value that measures the rate at which the expansion speed of the Universe varies with distance, and is one of the fundamental parameters of the Universe and allows, in particular, to determine the age of the Universe as we will see.

6 0

2 years ago

Complete each statement about the sign of the work done on a baseball. Carlton catches a baseball and his hand moves backward as

dezoksy [38]

Answer and Explanation:

The work done is negative as the force is applied in the forward direction and the displacement of the hand is in the backward direction.
The work done is positive as the work is done on the baseball by Carlton. Moreover, both the force applied and the displacement of Carlton are in a straight line in the forward direction.
The work done in this case is zero as Carlton rides with constant speed, the Kinetic energy too remains constant and hence net work done is zero.
The work done in this case is positive as the work is done on the baseball by Carlton and as the velocity changes its Kinetic energy also varies wit it.
Also the force applied and the displacement of Carlton in this case are in the directed to the same path.

8 0

2 years ago