All categories

2 years ago

Timed! I would really appreciate some help! thank you!

Physics

1 answer:

GenaCL600 [577]2 years ago

4 0

Answer:

x = 5[km]

Explanation:

We must convert the time from minutes to hours.

$t=30[min]*\frac{1h}{60min}= 0.5[h]\\$

We know that speed is defined as the relationship between space and time.

$v=x/t$

where:

x = space [m]

t = time = 0.5 [h]

v = velocity [m/s]

Now replacing:

$x = 10[\frac{km}{h} ]*0.5[h]\\x=5[km]$

You might be interested in

Which one of the statements below is true about mechanical waves?

ratelena [41]

Answer:

D) Mechanical waves require a medium for transmission (wire, air, etc.) as opposed to electromagnetic which travel through empty space - light, radio, etc.)

3 0

3 years ago

Two swimmers A and B, of weight 190 lb and 125 lb, respectively, are at diagonally opposite corners of a floating raft when they

Harrizon [31]

Answer:

a) 0.618 ft/s

b) 3.04 ft/s

Explanation:

Givens:

Weight of swimmer A $W_{A}$ = 190 Ib.

Weight of swimmer B $W_{B}$ = 125 Ib.

Weight of the raft $W_{R}$ = 300 Ib.

Swimmer A walks toward swimmer B relative to the raft with a speed

$V_{A/R}$ = 2 ft/s

a) Conservation of linear momentum

$m_{A} v_{A} +m_{B} v_{B} +m_{R} v_{R} =0..........(1)\\v_{A/R}=v_{A} -v_{R}\\\v_{A}=v_{A/R}+v_{R}.................(2)$

Since swimmer B does not move

$v_{B} =v_{R}...............(3)$

Substitute from (2) and (3) into (1)

$m_{A} (v_{A/R} +v_{R} )+m_{B} v_{R} +m_{R} v_{R}=0\\(m_{A}+m_{B}+m_{R})v_{R} =-m_{A}v_{A/R}\\v_{R}=\frac{-m_{A}v_{A/R}}{m_{A}+m_{B}+m_{R}} \\v_{R}=0.618ft/s$

b) if the raft not to move $v_{R}=0$

from (2)

$v_{A} =v_{A/R}$

substitute in (1)

$m_{A} v_{A/R} +m_{B} v_{B}+m_{R} (0)=0\\v_{B}=\frac{W_{A}v_{A/R}}{W_{B}} \\v_{B}=3.04ft/s$

3 0

3 years ago

an eagle has a mass of 8 kg and is flying 85 m above the ground with a speed of 20 m/s. what is the total mechanical energy of t

vivado [14]

Total Mechanical Energy = KE + PE

KE = (1/2)mv²

= (1/2)*8*20² = 1600 J

PE = mgh g ≈ 10 m/s²

= 8 * 10 * 85 = 6800J

Total Mechanical = 1600 + 6800 = 8400 J.

5 0

3 years ago

Two identical vertical springs S1 and S2 have masses m1 = 400 g and m2 = 800 g attached to them. If m1 causes spring S1 to stret

OlgaM077 [116]

Answer:

potential energy = mgh

= 400÷1000 × 10× 4÷100

= 0.4 × 10 × 0.04

=4/10 ×10×4/100

= 4/10 × 4/10

=16/100

= 0.16 joules

m1 (400) stretches 4cm

m1 (100g) stretches 1cm

so, m2(800g) stretches 8 cm

potential energy of m2 = mgh

= 800/1000 ×10×8/100

= 0.8 × 0.8

=8/10 ×8/10

= 64/100

=0.64 joules

Ratio of s1 to s2

16/100 ÷ 64/100

= 1:4 ( answer)

6 0

2 years ago

5.Projectile motion is free fall with an initial horizontal velocity. True or false

skelet666 [1.2K]

Explanation:

One of the interesting things about projectile motion is that the horizontal motion is independent of the vertical motion. Recall that in freefall, an object continually experiences a downward acceleration of 9.80ms2 but has no horizontal acceleration.

6 0

3 years ago