Can someone please help me?

A 1 170.0 kg car traveling initially with a speed of 25.000 m/s in an easterly direction crashes into the back of a 9 800.0 kg t

Stella [2.4K]

Answer:

Explanation:

mass of car, m1 = 1170 kg

mass of truck, m2 = 9800 kg

initial velocity of car, u1 = 25 m/s

initial velocity of truck, u2 = 20 m/s

final velocity of car, v1 = 18 m/s

Let the final velocity of truck is v2.

(a) Use the conservation of momentum

m1 x u1 + m2 x u2 + m1 x v1 + m2 x v2

1170 x 25 + 9800 x 20 = 1170 x 18 + 9800 x v2

29250 + 196000 = 21060 + 9800 v2

v2 = 20.84 m/s

(b) Total kinetic energy before collision,

Ki = 0.5 x 1170 x 25 x 25 + 0.5 x 9800 x 20 x 20

Ki = 365625 + 1960000 = 2325625 J

Total final kinetic energy

Kf = 0.5 x 1170 x 18 x 18 + 0.5 x 9800 x 20.84 x 20.84

Kf = 189540 + 2128097.44

Kf = 2317637.44 J

Change in energy = 2325625 - 2317637.44 = 7987.56 J

(c) It is due to the heat energy

4 0

4 years ago

A football was kicked so that it traveled 65 yards in 3.0 total seconds. What was the speed

Olin [163]

Answer:

vx = 65 yd/3 sec = 21.7 yd/sec since horizontal speed is constant

vy = g t = (32 / 3) yd/sec^2 * 1.5 sec = 16 yd/sec where 32/3 is the acceleration due to gravity in yds / sec^2 and 1.5 is the time to travel each way in the vertical direction

V = (vx^2 + vy^2)^1/2 = (21.7^2 + 16^2)^1/2 = 27 yd/sec

tan theta = vy/vx = 16 / 21.7 = .737 theta = 36.4 deg

You can check using the range formula:

R = v^2 sin (2 theta) / g = 27^2 * .955 / (32 / 3) = 65.3 yds

The difference from 65 yds may be rounding error.

4 0

4 years ago

Why is evaporation of water greater in summer?

tino4ka555 [31]

Evaporation of water is greater during the summer, because of the sever change of temperature (Depending where you live) and the increase of light rays on the earths surface, and bodies of water.

7 0

3 years ago

Read 2 more answers

Check<br> A current-carrying wire with many loops is called

Nadya [2.5K]

A current-carrying wire with many loops is called solenoid.

<u>Explanation:</u>

A current-carrying wire is a conductor. When it is turned into a coil for better use, it is called a solenoid. A solenoid has specific features. Since it is wrapped up in many turns, it creates a magnetic field inside. They also convert electric current into mechanical work or action.

The solenoid may or may not be straight. Anything wrapped into a coil is a solenoid. While the study, the length of a solenoid is taken greater than the diameter. And the shape is called a helix.

4 0

3 years ago

Read 2 more answers

Find the frequency of a tuning fork that takes2.50×10−3s to complete one oscillation.

maksim [4K]

The frequency of a tuning fork that takes2.50×10⁻³ s to complete one oscillation would be 400 Hz.

<h3>What is the frequency?</h3>

It can be defined as the number of cycles completed per second. It is represented in hertz and inversely proportional to the wavelength.

As given in the problem a tuning fork takes 2.50×10⁻³ s to complete one oscillation.

Frequency = 1/time period of the oscillation

Frequency of the tuning fork = 1/time period

=1/2.50×10⁻³

=400 Hz

Thus the frequency of a tuning fork comes out to be 400 Hz.

Learn more about frequency here, refer to the link;

brainly.com/question/14316711

#SPJ1

6 0

2 years ago