A 2000-kg truck traveling at a speed of 6.0 m/s slows down to 4.0 m/s along a straight road. What

Explain how the sun's position in the sky affects the length of shadows

Serggg [28]

A shadow forms on the side of an object that faces away from the sun. The length of shadows changes as Earth rotates. In the morning, the sun is low in the eastern sky and shadows are long. As time passes in the morning, the sun seems to move higher in the sky.

8 0

2 years ago

A bike rider pedals with constant acceleration to reach a velocity of 7.8 m/s over a time of 4.2 s. during the period of acceler

Artyom0805 [142]

To calculate the initial velocity of the bike, we use the following equation

$d=\frac{1}{2} (u+v)t$ .

or

$u=\frac{2d}{t} -v$

Here, u is initial velocity, v is final velocity, t is the time and d is the distance covered by bike.

Given, $u =7.8 m/s$ , $d= 19 m$ and $t=4.2 s$ .

Substituting these values in above equation, we get

$u = \frac{2 \times 19}{4.2 \ s} -7.8 m/s = 9.05 \ m/s - 7.8 \ m/s \\\\ u= 1.2 m/s$ .

Thus, the initial velocity of the bike is 1.2 m/s.

3 0

3 years ago

What is the maximum value the string tension can have before the can slips? The coefficient of static friction between the can a

Naya [18.7K]

Answer:

T= 38.38 N

Explanation:

Here

mass of can = m = 3 kg

g= 9.8 m/sec2

angle θ = 40°

From figure we see the vertical and horizontal component of tension force T

If the can is to slip - then horizontal component of tension force should become equal to force of friction.

First we find force of friction

Fs= μ R

where

μ = 0.76

R = weight of can = mg = 3 × 9.8 = 29.4 N

Now horizontal component of tension

Tx= T cos 40 = T× 0.7660 N

==>T× 0.7660 = 29.4

==> T= 38.38 N

8 0

3 years ago

What is warmer during the night: land or sea/ocean?

kupik [55]

I do believe the answer is land because the ocean/sea gets cold when its night. So the answer is land

5 0

2 years ago

Read 2 more answers

3. An athlete makes a long jump and follows a projectile motion. Air resistance is negligible. Which one of the following statem

yulyashka [42]

Answer:

Option (b) is correct.

Explanation:

The motion under the influence of gravity is called projectile motion.

The acceleration due to gravity is constant through out the motion and it is always acting downwards.

When an athlete jumps and follow the projectile path, it always have the same horizontal velocity as there is no acceleration in the horizontal direction.

Also he has the vertical acceleration constant which is equal to the acceleration due to gravity and acts towards the center of earth.

Option (b) is correct.

6 0

3 years ago